UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549





FORM 10-K





(Mark one)

[X] ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES

EXCHANGE ACT OF 1934

For the
fiscal year ended December 31, 2017

OR

[ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES

EXCHANGE ACT OF 1934

For the
transition period from
to

California Republic Auto Receivables Trust 2015-3

(Exact name of Issuing Entity as specified in its charter)

Central Index Key Number of Issuing Entity: 0001650526

Commission File Number of Issuing Entity: 333-199204-04

California Republic Funding, LLC

(Exact name of Depositor as specified in its charter)

Central Index Key Number of Depositor: 0001561326

Commission File Number of Depositor: 333-199204

Mechanics Bank

(Exact name
of Sponsor as specified in its charter)

Central Index Key Number of Sponsor: 0001603949



| |  |                                                                                  |  |                                    
| |  | -------------------------------------------------------------------------------- |  | -----------------------------------
| |  | Delaware                                                                         |  | 38-7143889                         
| |  | (State or other jurisdiction of incorporation or organization of Issuing Entity) |  | (I.R.S Employer Identification No.)
| |  |                                                                                 
| |  | 18400 Von Karman Avenue Suite 1100, Irvine, CA                                   |  | 92612                              
| |  | (Address of principal executive offices of Issuing Entity)                       |  | (Zip Code)                         

Telephone number, including area code of Issuing Entity: (949) 270-9700

Securities registered pursuant to Section 12(b) of the Act:        None

Securities registered pursuant to Section 12(g) of the Act:        None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the securities Act.

Yes [ ] No [X]

Indicate by check mark if the registrant is not
required to file reports pursuant to Section 13 or Section 15(d) of the Act.

Yes [ ] No [X]



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Indicate by check mark whether the registrant (1) has filed all reports required to be filed by
Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past
90 days.

Yes[X] No [ ]

Indicate by check mark whether the
registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of
this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).

Yes[X] No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§232.405
of this chapter) is not contained herein, and will not be contained, to the best of registrants knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form
10-K or any amendment to this Form 10-K.

Not applicable.

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated
filer, a smaller reporting company, or emerging growth company. See the definitions of large accelerated filer, accelerated filer, smaller reporting company, and emerging growth company in Rule 12b-2 of the Exchange Act. (Check One):

|                                                                        |  |                              
|----------------------------------------------------------------------- |  | -----------------------------
|Large Accelerated Filer [ ]                                             |  | Accelerated Filer [ ]        
|                                                                        | 
|Non-Accelerated Filer [X]
(Do not check if a smaller reporting company) |  | Smaller reporting company [ ]
|                                                                        | 
|Emerging growth company [ ]                                             |  |                              

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period
for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.    [ ]

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).

Yes [ ] No [X]

State the aggregate market value of the voting
and non-voting common equity held by non-affiliates computed by reference to the price at which the common equity was last sold, or the average bid and asked price of
such common equity, as of the last business day of the registrants most recently completed second fiscal quarter.

Not applicable.

Documents Incorporated By Reference

List hereunder the
following documents if incorporated by reference and the part of the Form 10-K (e.g., Part I, Part II, etc.) into which the document is incorporated: (1) Any annual report to security holders;
(2) Any proxy information statement; and, (3) Any prospectus filed pursuant to Rule 424(b) or (c) under the Securities Act of 1933.

None.



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PART I

The following items have been omitted from Part I in accordance with general instruction J(1) to Form 10-K:

Item 1. Business.

Item 1A. Risk Factors.

Item 2. Properties.

Item 3. Legal Proceedings.

Item 4. Mine Safety Disclosures.

Item 1B. Unresolved Staff
Comments.

None.

PART II

The following items have been omitted from Part II in accordance with general instruction J(1) to Form 10-K:

Item 5. Market for Registrants Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

Item 6. Selected Financial Data.

Item 7. Managements
Discussion and Analysis of Financial Condition and Results of Operation.

Item 7A. Quantitative and Qualitative Disclosures about Market Risk.

Item 8. Financial Statements and Supplementary Data.

Item 9.
Changes in and Disagreements with Accountants on Accounting and Financial Disclosure.

Item 9A. Controls and Procedures.

Item 9B. Other Information.

None.

PART III

The following items have
been omitted from Part III in accordance with general instruction J(1) to Form 10-K:

Item 10. Directors,
Executive Officers and Corporate Governance.

Item 11. Executive Compensation.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

Item 13. Certain Relationships and Related Transactions, and Director Independence.



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Item 14. Principal Accounting Fees and Services.

The following substitute information is provided in accordance with General Instruction J(2) to Form 10-K:

Item 1112(b) of Regulation AB. Significant Obligors of Pool Assets (Financial Information)

No single obligor represents more than 10% of the pool assets held by California Republic Auto Receivables Trust
2015-3 (the Trust).

Item 1114(b)(2) of Regulation AB. Credit Enhancement and Other Support
Except for Certain Derivatives Instruments (Information Regarding Significant Enhancement Providers)

None.

Item 1115(b) of Regulation AB. Certain Derivative Instruments (Financial Information)

No entity or group of affiliated entities provides any derivative instruments that are used to alter payments characteristics of the cash flows from the
Trust.

Item 1117 of Regulation AB. Legal Proceedings

No legal proceedings are pending against any of Mechanics Bank (the Sponsor), California Republic Funding, LLC (the Depositor), or the
Trust, or against any property of any such entities that are or would be material to holders of the Notes or certificates (the Certificates) issued by the Trust.

U.S. Bank National Association (U.S. Bank), the Indenture Trustee with respect to the Trust, has provided the following disclosure:

Since 2014 various plaintiffs or groups of plaintiffs, primarily investors, have filed claims against U.S. Bank National Association (U.S. Bank),
in its capacity as trustee or successor trustee (as the case may be) under certain residential mortgage backed securities (RMBS) trusts. The plaintiffs or plaintiff groups have filed substantially similar complaints against other RMBS
trustees, including Deutsche Bank, Citibank, HSBC, Bank of New York Mellon and Wells Fargo. The complaints against U.S. Bank allege the trustee caused losses to investors as a result of alleged failures by the sponsors, mortgage loan sellers and
servicers for these RMBS trusts and assert causes of action based upon the trustees purported failure to enforce repurchase obligations of mortgage loan sellers for alleged breaches of representations and warranties concerning loan quality.
The complaints also assert that the trustee failed to notify security holders of purported events of default allegedly caused by breaches of servicing standards by mortgage loan servicers and that the trustee purportedly failed to abide by a
heightened standard of care following alleged events of default.

Currently U.S. Bank is a defendant in multiple actions alleging individual or class
action claims against the trustee with respect to multiple trusts as described above with the most substantial case being: BlackRock Balanced Capital Portfolio et al v. U.S. Bank National Association, No. 605204/2015 (N.Y. Sup. Ct.) (class
action alleging claims with respect to approximately 770 trusts) and its companion case BlackRock Core Bond Portfolio et al v. U.S Bank National Association, No.
14-cv-9401 (S.D.N.Y.). Some of the trusts implicated in the aforementioned Blackrock cases, as well as other trusts, are involved in actions brought by separate groups
of plaintiffs related to no more than 100 trusts per case.

U.S. Bank cannot assure you as to the outcome of any of the litigation, or the possible impact
of these litigations on the trustee or the RMBS trusts. However, U.S. Bank denies liability and believes that it has performed its obligations under the RMBS trusts in good faith, that its actions were not the cause of losses to investors and that
it has meritorious defenses, and it intends to contest the plaintiffs claims vigorously.

.



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Item 1119 of Regulation AB. Affiliations and Certain Relationships and Related Transactions.

The Sponsor is the originator, as contemplated by Item 1110 of Regulation AB, of all the pool assets owned by the Trust. The Sponsor is also the servicer. The
Depositor is a wholly-owned subsidiary of the Sponsor and, therefore, a wholly-owned subsidiary of the originator and the servicer.

The Indenture Trustee
is not affiliated with the Sponsor (including in its role as originator and servicer), the Depositor, or the Trust. The Owner Trustee is not affiliated with the Sponsor or the Depositor.

There are no significant obligors or support providers, or other material parties related to the Notes or Certificates.

In addition, there are no business relationships, agreements, arrangements, transactions or understanding outside the ordinary course of business or on terms
other than would be obtained in an arms length transaction with an unrelated party, apart from the transaction involving the issuance of the Notes and Certificates by the Trust, between the Sponsor, the Depositor or the Trust and any of the
parties mentioned in this Item.

Item 1122 of Regulation AB. Compliance with Applicable Servicing Criteria.

The Sponsor (in its role as servicer), and the Indenture Trustee (the Sponsor, as servicer, and the Indenture Trustee collectively as the Servicing
Participants) have each been identified by the Depositor as participating in the servicing function with respect to the asset pool held by the Trust. The Servicing Participants have each completed a report on an assessment of compliance with
its respective servicing functions (each, a Servicing Report), which Servicing Reports are attached as exhibits to this Form 10-K. Neither the Servicing Reports prepared by any of the Servicing
Participants, nor the Attestation Reports provided by the Servicing Participants respective registered public accounting firms have identified any material instance of noncompliance with the servicing criteria applicable to the respective
Servicing Participant.

Item 1123 of Regulation AB. Servicer Compliance Statement.

The Sponsor (in its role as servicer) has been identified by the Depositor as a servicer with respect to the asset pool held by the Trust. The Sponsor has
completed a statement of compliance with applicable servicing criteria (the Compliance Statement), signed by an authorized officer of the Sponsor. The Compliance Statement is attached as an exhibit to this Form 10-K.

PART IV

Item 15. Exhibits, Financial Statement Schedules.

(a)    (1) Financial Statements:  Not applicable.

(2) Financial Statement Schedules:  Not applicable

(3) List of Exhibits



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The following exhibits are provided as part of, and incorporated by reference into, this Annual
Report on Form 10-K:



|        |  |                                                                                                                                                                   |  |               
|------- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | --------------
|Exhibit |  | Description                                                                                                                                                       |  |               
|        |  |                                                                                                                                                                  
|3.1     |  | Depositors Certificate of Formation                                                                                                                              |  | *             
|        |  |                                                                                                                                                                  
|3.2     |  | Depositors Operating Agreement                                                                                                                                   |  | *             
|        |  |                                                                                                                                                                  
|4.1     |  | Amended and Restated Trust Agreement                                                                                                                              |  | **            
|        |  |                                                                                                                                                                  
|4.2     |  | Indenture                                                                                                                                                         |  | **            
|        |  |                                                                                                                                                                  
|10.1    |  | Sale and Servicing Agreement                                                                                                                                      |  | **            
|        |  |                                                                                                                                                                  
|10.2    |  | Administration Agreement                                                                                                                                          |  | **            
|        |  |                                                                                                                                                                  
|10.3    |  | Receivables Purchase Agreement                                                                                                                                    |  | **            
|        |  |                                                                                                                                                                  
|31      |  | Section 302 Certification                                                                                                                                         |  | Filed herewith
|        |  |                                                                                                                                                                  
|33.1    |  | Managements Report on assessment of Compliance with SEC Regulation AB Servicing Criteria                                                                         |  | Filed herewith
|        |  |                                                                                                                                                                  
|33.2    |  | Indenture Trustees Assertion of Compliance                                                                                                                       |  | Filed herewith
|        |  |                                                                                                                                                                  
|34.1    |  | Report of Independent Registered Public Accounting Firm (Crowe Horwath LLP on behalf of Mechanics Bank)                                                           |  | Filed herewith
|        |  |                                                                                                                                                                  
|34.2    |  | Report of Independent Registered Public Accounting Firm (Ernst & Young LLP on behalf of Indenture Trustee)                                                        |  | Filed herewith
|        |  |                                                                                                                                                                  
|35      |  | Servicing Compliance Report of Mechanics Bank as Servicer                                                                                                         |  | Filed herewith
|        |  |                                                                                                                                                                  
|*       |  | Incorporated herein by reference to the corresponding Exhibit to California Republic LLCs Registration Statement filed on August 28, 2013 (File
No. 333-190866). |  |               
|        |  |                                                                                                                                                                  
|**      |  | Incorporated herein by reference to the corresponding Exhibit to the Form 8-K filed on September 29, 2015 (File No. 333-199204-04).                               |  |               

(b)    Exhibits.

The Depositor hereby is providing as part of this Annual Report on Form 10-K the exhibits listed in
Item 15(a)(3) set forth above.

(c)    Financial Statement Schedule.

Not Applicable.



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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Depositor has duly caused this report to be signed on its
behalf by the undersigned, thereunto duly authorized.

California Republic Funding, LLC, as Depositor



|                                        |  |                   
|--------------------------------------- |  | ------------------
|                                        | 
|By:                                     |  | /s/ Nathan J. Duda
|Nathan J. Duda, Chief Financial Officer
|Dated: March 29, 2018