|  Filed                Pursuant to Rule 424(b)(3)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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|  Registration                No. 333-124310                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| PRICING                SUPPLEMENT NO. 420                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Dated                May 11, 2007 to                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| PROSPECTUS                SUPPLEMENT                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| Dated                June 8, 2005 and                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| PROSPECTUS                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| Dated                May 13, 2005                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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| CATERPILLAR                FINANCIAL SERVICES CORPORATION                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| MEDIUM-TERM                NOTES, SERIES F, FLOATING RATE NOTES DUE 2009                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
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| **SUBJECT**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | **FINAL                PRICING DETAILS** |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| Issuer:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                | Caterpillar                Financial Services Corporation |
| Title                of Securities:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | Medium-Term                Notes, Series F, Floating Rate Notes Due 2009 |
| Form                of Security:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | Global                Note |
| Ratings:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               | A2/A |
| Format:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                | SEC                Registered-Registration Statement Number 333-124310 |
| Trade                Date/Pricing Effective Time:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | May                8, 2007 |
| Settlement                Date (Original Issue date):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | May                15, 2007 |
| Maturity                Date:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | May                15, 2009 |
| Principal                Amount:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | $500,000,000 |
| Price                to Public (Issue Price):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | 100.00% |
| Dealers'                Commission:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | 00.10%                (10 basis points) |
| All-in-price:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | 99.900% |
| Net                Proceeds to Issuer:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | $499,500,000 |
| Interest                Rate Basis (Benchmark):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 3                Month USD LIBOR, as determined by LIBOR Telerate |
| Index                Currency:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | U.S.                Dollars |
| Spread                (Plus or Minus):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | +                0                basis points (0.00%) |
| Spread                Multiplier:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | N/A |
| Spread/Spread                Multiplier Reset Option:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | N/A |
| Optional                Reset Dates (only applicable if option to reset spread or spread                multiplier):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | N/A |
| Basis                for Interest Rate Reset (only applicable if option to reset spread                or                spread multiplier):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | N/A |
| Index                Maturity:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Three                Months |
| Interest                Rate Calculation:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | USD                LIBOR determined on Interest Determination Date plus the                Spread |
| Specified                Currency:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     | U.S.                Dollars |
| Option                to Elect Payment in U.S. Dollars (only applicable if Specified Currency                is                other than U.S. Dollars):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               | N/A |
| Authorized                Denominations (only applicable if Specified Currency is other than                U.S.                Dollars):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | N/A |
| Historical                Exchange Rate (only applicable if Specified Currency is other than                U.S.                Dollars):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | N/A |
| Initial                Interest Rate:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | To                be determined two (2) London Business Days prior to the Original                Issue                Date |
| Maximum                Interest Rate:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | N/A |
| Minimum                Interest Rate:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | N/A |
| Interest                Reset Periods and Dates:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | Quarterly                on the 15th of each February, May, August and November of each year                prior |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | to                the Maturity Date, subject to Modified Following Business Day                convention |
| Interest                Determination Dates:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | Quarterly,                two London Business Days prior to each Interest Reset                Date |
| Interest                Payment Dates:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | Interest                will be paid quarterly on the 15th of each February, May, August                and                November |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | of                each year, commencing August 15, 2007 and ending on the Maturity                Date |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |   |
| Stated                Maturity Extension Option:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | N/A |
| Extension                Period(s) and Final Maturity Date (only applicable if option to extend                stated maturity):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | N/A |
| Basis                for Interest Rate During Extension Period (only applicable if option                to                extend stated maturity):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | N/A |
| Original                Issue Discount Note:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | N/A |
| Total                Amount of OID:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | N/A |
| Terms                of Amortizing Notes:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | N/A |
| Redemption                Date(s):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     | N/A |
| Redemption                Price:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | N/A |
| Repayment                Date(s):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | N/A |
| Repayment                Price(s):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     | N/A |
| Day                Count Convention:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Actual/360 |
| Denominations:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Minimum                denominations of $1,000 with increments of $1,000                thereafter |
| Bookrunners:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | Barclays                Capital (70.00%) |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Citigroup                Global Markets Inc. (30.00%) |
| Exchange                Rate Agent:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | U.S.                Bank Trust National Association |
| Calculation                Agent:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | U.S.                Bank Trust National Association |
| CUSIP:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 14912L3J8 |
| Other                Terms:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | N/A |
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| **CAPITALIZED                TERMS USED HEREIN WHICH ARE DEFINED IN THE PROSPECTUS SUPPLEMENT                SHALL                HAVE THE MEANINGS ASCRIBED THERETO IN THE PROPSECTUS SUPPLEMENT.                THE                INTEREST RATES ON THE NOTES MAY BE CHANGED BY CATERPILLAR FINANCIAL                SERVICES CORPORATION FROM TIME TO TIME, BUT ANY SUCH CHANGE WILL                NOT                AFFECT THE INTEREST RATE ON ANY NOTES OFFERED PRIOR TO THE EFFECTIVE                DATE                OF THE CHANGE. AFTER THE ISSUANCE OF THE NOTES COVERED BY THIS PRICING                SUPPLEMENT, $4,100 MM PRINCIPAL AMOUNT OF NOTES REMAIN AVAILABLE                FOR SALE                PURSUANT TO THE ACCOMPANYING PROSPECTUS SUPPLEMENT.** |
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