EXHIBIT 4.6

AMENDMENT NUMBER 2  TO INDENTURE

THIS
AMENDMENT NUMBER 2 TO INDENTURE (this "Amendment"), dated as of January 14, 2004 (the "Effective
Date") amends that certain Indenture, dated as of December 31, 2002 (as amended, modified or supplemented from time to time as permitted thereby, the
"Indenture") by and between BRL Universal Compression Funding I 2002, L.P. (the "Issuer") and Wells
Fargo Bank, National Association, successor by merger to Wells Fargo Bank Minnesota, National Association, as indenture trustee (the "Indenture
Trustee").

W
I T N E S S E T H:

WHEREAS,
the Issuer and the Indenture Trustee have previously entered into the Indenture;

WHEREAS,
the parties desire to amend the Indenture in order to modify certain provisions of the Indenture;

NOW
THEREFORE, in consideration of the premises and mutual covenants herein contained, the parties hereto agree as follows:

SECTION
1.Defined Terms. Capitalized terms used in this Amendment and not otherwise defined herein shall have the meanings assigned in
the Indenture.

SECTION
2.Full Force and Effect. Other than as specifically modified hereby, the Indenture shall remain in full force and effect in
accordance with the terms and provisions thereof and is hereby ratified and confirmed by the parties hereto.

SECTION
3.Amendments to the Indenture. Pursuant to Section 1002 of the Indenture, as of the Effective Date, the following
amendments are being made to the Indenture:

(a)   The
definition of "Scheduled Deposit Amount" is hereby deleted in its entirety and the following shall be substituted in place thereof:



|Scheduled Deposit Amount                 |  | = |  | Target Level  (Current Cash Balance + Purchase Option Payments)                                                                                                                      
|---------------------------------------- |  | - |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|Where:                                   |  |   |  |                                                                                                                                                                                       
|Target Level                             |  | = |  | Commitment Termination Date Target Level + (68% × DV of Sold Equipment) + (68% × DV of Excess Concentration Equipment) + (68% × DV of Excess Aged Equipment)                          
|                                         |  |   |  | The Target Level is capped at the Aggregate Outstanding Amounts as of the Commitment Termination Date.                                                                                
|Commitment Termination Date
Target Level |  | = |  | MRPA  Commitment Termination Date Cash ) x Months
Balance                                        
                                Elapsed;
                              Total Months
|                                         |  |   |  | + the Commitment Termination Date Cash Balance                                                                                                                                        
|                                         |  |   |  |                                                                                                                                                                                       

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|DV of Sold Equipment                     |  | = |  | The excess, if any, of (1) the sum of Depreciated Values of all Head Lessee Compressors that have been sold following the Commitment Termination Date up to the succeeding Rent Payment Date over (2) the sum of the Depreciated Values of the Eligible
Compressors subject to Eligible Leases that have been contributed to the Head Lessee following the Commitment Termination Date up to the succeeding Rent Payment Date.
|---------------------------------------- |  | - |  | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|DV of Excess Concentration Equipment     |  | = |  | The sum of all Excess 99 hp Amounts, the Excess 299 hp Amounts, the Excess 599 hp Amounts, the Excess 999 hp Amounts, the Excess Investment Grade Lessee Concentration Amounts, the Excess BB Lessee Concentration Amounts, the Excess B Lessee
Concentration Amounts and the Excess Top 3 Lessee Concentration Amounts.                                                                                                      
|DV of Excess Aged Equipment              |  | = |  | All Excess Aged Equipment Amounts.                                                                                                                                                                                                                                                                                                                                                                                            
|Current Cash Balance                     |  | = |  | The total amount of funds then on deposit in the Collateral Account.                                                                                                                                                                                                                                                                                                                                                          
|Purchase Option Payments                 |  | = |  | The aggregate amount that the Head Lessee has paid to the Head Lessor following the Commitment Termination Date in connection with any exercise of the Head Lessee's purchase option, whether at the end of the Term or otherwise.                                                                                                                                                                                            
|MRPA                                     |  | = |  | 80% of the initial Appraised Value of all Head Lessor Compressors owned by the Head Lessor on the Commitment Termination Date.                                                                                                                                                                                                                                                                                                
|Commitment Termination Date Cash Balance |  | = |  | The amount on deposit in the Collateral Account on the Commitment Termination Date.                                                                                                                                                                                                                                                                                                                                           
|Months Elapsed                           |  | = |  | The cumulative number of months elapsed from the Commitment Termination Date to the date of determination (inclusive).                                                                                                                                                                                                                                                                                                        
|Total Months                             |  | = |  | The total number of months from the Commitment Termination Date to the Termination Date (inclusive)."                                                                                                                                                                                                                                                                                                                         

(b)   Subsection
(iii) in the definition of "Series 2002-1 Note Commitment Termination Date" is hereby deleted in its entirety and the following
shall be substituted in place thereof:



(c)   The
first sentence of Section 702(b) of the Indenture is hereby deleted in its entirety and the following shall be substituted in place thereof:



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SECTION
4.Representations and Warranties. In order to induce the Deal Agent, the Series Enhancer, the Interest Rate Hedge Provider and
the Control Party to enter into this Amendment, each of the Issuer and the Indenture Trustee hereby represents and warrants unto each of the Deal Agent, the Series Enhancer, the Interest Rate Hedge
Provider and the Control Party as set forth in this Section 4:

(a)   Each
of the Issuer and the Indenture Trustee hereby confirms that each of the representations and warranties set forth in Articles V and VI and Section 911, as
applicable, of the Indenture are true and correct as of the Effective Date with the same effect as though each had been made as of such date, except to the extent that any of such representations and
warranties expressly relate to earlier dates in which case such representations and warranties shall be correct as of such earlier date.

(b)   The
Issuer represents and warrants that, immediately prior to the effectiveness of, and after giving effect to, the amendments contemplated hereby, no Event of Default,
Manager Default, Head Lease Event of Default, Universal Event, Trigger Event or Prospective Trigger Event has occurred and is continuing.

(c)   Each
of the Issuer and the Indenture Trustee hereby represents and warrants to the parties hereto that it possesses all requisite power and authority to execute, and
deliver, and to perform each of its obligations under this Amendment and to effect the transactions contemplated hereby, all of which have been duly authorized and approved by all necessary limited
partnership or corporate action, as applicable, and for which no consent of any Governmental Authority or any other person is required, and agrees to furnish the Deal Agent with evidence of such
authorization and approval upon request.

(d)   No
authorization or approval or other action by, and no notice to or filing with, any governmental authority or regulatory body or other Person is required for the due
execution, delivery or performance by any of the Issuer and the Indenture Trustee of this Amendment or any other documents to be executed by any of the Issuer and the Indenture Trustee in connection
with this Amendment.

(e)   This
Amendment constitutes, and each other document executed by each of the Issuer and the Indenture Trustee in connection with this Amendment will, upon the due
execution and delivery thereof, constitute, the legal, valid and binding obligations of each of the Issuer and the Indenture Trustee enforceable in accordance with its terms.

SECTION
5.Conditions Precedent. The effectiveness of this Amendment shall be upon satisfaction of each of the conditions set forth in
this Section 5:

(a)   The
Deal Agent has received counterparts of this Amendment and such related documentation as the Deal Agent or its counsel shall determine in their reasonable
discretion, in form and substance satisfactory to the Deal Agent, duly executed and delivered by the Issuer, the Indenture Trustee, the Deal Agent, the Interest Rate Hedge Provider and the Series
Enhancer, as applicable;

(b)   The
Deal Agent has received a certificate from the Issuer dated as of the Effective Date stating that (i) all representations and warranties of the Issuer set
forth in the Indenture, as amended

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hereby,
each of the other Related Documents, and this Amendment are true and correct; and (ii) no Event of Default, Manager Default, Head Lease Event of Default, Universal Event, Trigger Event
or Prospective Trigger Event has occurred and is continuing;

(c)   The
Deal Agent has received certified resolutions of the Issuer approving this Amendment and the other documents executed in connection herewith and certifying as of the
Effective Date; the names and true signatures of persons authorized to sign this Amendment on behalf of the Issuer;

(d)   No
Event of Default, Manager Default, Head Lease Event of Default, Universal Event, Trigger Event or Prospective Trigger Event has occurred and is continuing; and

(e)   That
certain Amendment Number 1 to the Head Lessee Security Agreement, that certain Amendment Number 1 to the Irrevocable Letter of Credit No. SM201468W, that certain
Amendment Number 2 to Amended and Restated Agreement of Limited Partnership of BRL Universal Compression Funding I 2002, L.P. and that certain Amendment Number 2 to Series 2002-1
Note Purchase Agreement shall each be effective.

SECTION
6.Miscellaneous Provisions.

(a)   This
Amendment shall become effective as of the Effective Date.

(b)   This
Amendment shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns.

(c)   On
and after the execution and delivery hereof, (i) this Amendment shall be a part of the Indenture, and (ii) each reference in the Indenture to "this
Indenture" or "hereof", "hereunder" or words of like import, and each reference in any other document to the Indenture shall mean and be a reference to the Indenture as amended or modified hereby.

SECTION
7.Execution in Counterparts. This Amendment may be executed by the parties hereto in separate counterparts, each of which shall
be deemed to be an original and all of which shall constitute together but one and the same agreement.

SECTION
8.Governing Law. THIS AMENDMENT SHALL BE CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO
CONFLICT OF LAW PRINCIPLES, PROVIDED THAT SECTIONS 5-1401 AND 5-1402 OF THE NEW YORK GENERAL OBLIGATIONS LAW SHALL APPLY, AND THE OBLIGATIONS, RIGHTS AND REMEDIES OF THE
PARTIES HEREUNDER SHALL BE DETERMINED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

[Signature Page to Follow]

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IN
WITNESS WHEREOF, the parties hereto have executed and delivered this Amendment on the date first above written and ratify and consent to that certain Amendment Number 1 to Indenture,
dated as of December 18, 2003.

| |  | ISSUER:                                                                                                        
| |  | ---------------------------------------------------------------------------------------------------------------
| |  | BRL UNIVERSAL COMPRESSION FUNDING I 2002, L.P.                                                                 
| |  | By:                                                                                                            
| |  |                                                                                                                
| |  |                                                                                                                
| |  |                                                                                                                
| |  | INDENTURE TRUSTEE:                                                                                             
| |  | WELLS FARGO BANK, NATIONAL ASSOCIATION, SUCCESSOR BY MERGER TO WELLS FARGO BANK MINNESOTA, NATIONAL ASSOCIATION
| |  | By:                                                                                                            
| |  | Name:                                                                                                          
| |  | Title:                                                                                                         

In
accordance with Section 1002 of the Indenture, the undersigned hereby consent to this Amendment and ratify and consent to that certain Amendment Number 1 to Indenture, dated as
of December 18, 2003.

|DEAL AGENT:                   |  |                     
|----------------------------- |  | --------------------
|WACHOVIA CAPITAL MARKETS, LLC |  |                     
|By:                           |  | /s/ Spencer Langston
|Name:                         |  | Spencer Langston    
|Title:                        |  | Vice President      

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|NOTEHOLDER:                          |  |                                                   
|------------------------------------ |  | --------------------------------------------------
|VARIABLE FUNDING CAPITAL CORPORATION |  |                                                   
|By:                                  |  | WACHOVIA CAPITAL MARKETS, LLC
Its attorney-in-fact
|                                     |  | By:                                               
|                                     |  | Name:                                             
|                                     |  | Title:                                            

In
accordance with Sections 608 and 1002 of the Indenture, the undersigned hereby consent to this Amendment and ratify and consent to that certain Amendment Number 1 to Indenture, dated
as of December 18, 2003.

|INTEREST RATE HEDGE PROVIDER:       |  |                        
|----------------------------------- |  | -----------------------
|WACHOVIA BANK, NATIONAL ASSOCIATION
|By:                                 |  | /s/ Matthew Magidson   
|Name:                               |  | Matthew Magidson       
|Title:                              |  | Vice President         
|CONTROL PARTY AND SERIES ENHANCER: 
|AMBAC ASSURANCE CORPORATION        
|By:                                 |  | /s/ Jennifer J. Baratta
|Name:                               |  | Jennifer J. Baratta    
|Title:                              |  | Vice President         

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