THIRD AMENDMENT AGREEMENT To Omnibus Pledge and Security Agreement and Irrevocable Proxy Dated as of June 5, 2009 by and among

Exhibit 10.28

EXECUTION COPY

THIRD AMENDMENT AGREEMENT

To Omnibus Pledge and Security Agreement and Irrevocable Proxy

Dated as of June 5, 2009

by and among

RFC ASSET HOLDINGS II, LLC,

PASSIVE ASSET TRANSACTIONS, LLC

RESIDENTIAL CAPITAL, LLC

RESIDENTIAL FUNDING COMPANY, LLC

GMAC MORTGAGE, LLC

and certain of their Affiliates from time to time parties hereto,

as Grantors,

GMAC INVESTMENT MANAGEMENT LLC,

as a Secured Party

and

GMAC LLC,

as Omnibus Agent, as Lender Agent under the Loan Agreement,

as Lender under the MSR Loan Agreement, as Credit Agent under the Credit Agreement

and as a Secured Party

This THIRD AMENDMENT AGREEMENT (this “ Agreement ”) dated as of June 5, 2009 (the “ Amendment Effective Date ”), is by and among RFC Asset Holdings II, LLC, a Delaware limited liability company (“ RAHI ”), and Passive Asset Transactions, LLC, a Delaware limited liability company (“ PATI ”); Residential Capital, LLC, a Delaware limited liability company (“ ResCap ”), Residential Funding Company, LLC, a Delaware limited liability company (“ RFC ”), and GMAC Mortgage, LLC, a Delaware limited liability company (“ GMAC Mortgage ” and each of RAHI, PATI, ResCap, and RFC, together with any successors and assigns, is herein a “ Grantor ” and collectively, the “ Grantors ”); GMAC Investment Management LLC, a Delaware limited liability company (together with its successors and assigns, “ GMAC IM ”), as a Secured Party; and GMAC LLC, a Delaware limited liability company, as agent for the Secured Parties (in such capacity, the “ Omnibus Agent ”), as Lender Agent under the Loan Agreement, as Lender under the MSR Loan Agreement, as Credit Agent under the Credit Agreement and as a Secured Party.

Reference is hereby made to the Omnibus Pledge and Security Agreement and Irrevocable Proxy dated as of March 18, 2009 among the Grantors, GMAC IM and the Omnibus Agent (as amended and modified through the date hereof, the “ Omnibus Security Agreement ”).

RECITALS

1. Each of the parties hereto is a party to the Omnibus Security Agreement.

2. The parties hereto desire to make certain amendments to the Omnibus Security Agreement.

3. Each of the parties hereto, by its signature hereto, hereby acknowledges, consents and agrees to the changes set forth herein.

4. In consideration of the promises and mutual agreements herein contained and for good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the parties hereto agree as follows:

ARTICLE I

DEFINED TERMS

SECTION 1.1 Capitalized terms used herein and not otherwise defined shall have the meaning set forth in the Omnibus Security Agreement.

ARTICLE II

AMENDMENTS TO THE OMNIBUS SECURITY AGREEMENT

SECTION 2.1 Amendment to Section 1 . The following definitions are hereby amended and restated in their entirety to read as follows:

“ Contribution Agreement means, as the case may be, (a) that certain Contribution Agreement dated as of November 20, 2008, among ResCap, GMAC Residential Holding Company, LLC, GMAC Mortgage, and PATI; (b) that certain Contribution Agreement dated as of November 20, 2008, among RAHI, PATI, RAHI A, LLC and PATI A, LLC; or (c) that certain Contribution Agreement dated as of June 2, 2009, among ResCap, GMAC Residential Holding Company, LLC, GMAC Mortgage, and PATI, in each case as the same may be amended, supplemented, restated or otherwise modified from time to time; and Contribution Agreements means all of them.

GX II Security Documents means the GX II Administration Agreement, the GX II Guaranteed Investment Contract, the GX II Trust Deed, GX II VFLN Agreement, the GX II Notes and each other document, agreement and deed entered into by ResCap, its Subsidiary, GX II SPE and/or the Stichting Security Trustee GX CE Funding II in connection with the purchase of certain residential mortgage loans and related assets, the issuance of the GX II Notes and creation of security in respect of the GX II Notes in favor of the Stichting Security Trustee GX CE Funding II, in each case, by the GX II SPE, as all of the foregoing may be amended, supplemented, restated or otherwise modified from time to time, and in each case if and to the extent any of the foregoing evidence or relate to the GX II Notes.”

SECTION 2.2 Amendment to Section 2 . Section 2 of the Omnibus Security Agreement is hereby amended and restated to read as follows:

“2. Grant of Security Interest by Grantors . As security for the prompt payment in full in cash and performance of all Obligations, each of the Grantors hereby pledges to the Omnibus Agent and hereby grants a continuing security interest to the Omnibus Agent in all of each such Grantor’s right, title and interest, in, to, and under, whether now or hereafter existing, owned or acquired and wherever located and howsoever created, arising or evidenced, all of the following:

(a) all Pledged Mortgage Loans and all assets, rights or property related thereto;

(b) all Pledged Shares of each Pledged Share Issuer identified in Exhibit B of Schedule IV hereto and all assets, rights or property related thereto;

(c) (i) all Flume No. 8 Notes, all GX II Notes, all First Savings Warehouse Notes, all Provident Warehouse Notes and all other Pledged Notes (including, without limitation, the Flume No. 8 Initial Note and the GX II Initial Note), and (ii) all assets, rights or property related thereto (including, without limitation, the Flume No. 8 Facility Documents, the Warehouse Loans, the Warehouse Facility Documents, the GX II Security Documents, and all Pledged Note Liens, if and to the extent the foregoing evidence or relate to the Flume No. 8 Notes, the GX II Notes or such other Pledged Notes);

(d) (i) all Pledged Interests (including, without limitation, the equity interests owned by RAHI in RAHI A, LLC, a Delaware limited liability company, by PATI in PATI A, LLC, a Delaware limited liability company and by RFC in Equity Investment I, LLC, a Delaware limited liability company), and (ii) all assets, rights or property related thereto;

(e) (i) all Dividends, Distributions, interest, and (ii) other payments and rights, in each case if and to the extent evidencing or related to the Pledged Shares, Pledged Notes and Pledged Note Liens, Pledged Interests, Flume No. 8 Facility Documents, GX II Security Documents, Warehouse Loans, Warehouse Facility Documents or Pledged Mortgage Loans;

(f) all Deposit Accounts, including, without limitation, all Deposit Accounts identified on Exhibit A of Schedule IV , and all Property deposited or carried therein or credited thereto, in each case if and to the extent related to any Pledged Shares, Pledged Notes and Pledged Note Liens, Pledged Interests, Flume No. 8 Facility Documents, GX II Security Documents, Warehouse Loans, Warehouse Facility Documents or Pledged Mortgage Loans;

(g) all Securities Accounts including, without limitation, all Securities Accounts identified on Exhibit A of Schedule IV , and all Property, including all Investment Property and Financial Assets, deposited or carried therein or credited thereto, and all permitted investments acquired with funds on deposit in or carried in or credited to such Securities Accounts, in each case if and to the extent related to any Pledged Shares, Pledged Notes and Pledged Note Liens, Pledged Interests, Flume No. 8 Facility Documents, GX II Security Documents, Warehouse Loans, Warehouse Facility Documents or Pledged Mortgage Loans;

(h) to the extent not included in the foregoing, the Contribution Agreements and all other agreements, contracts, documents and instruments if and to the extent evidencing or related to any Pledged Shares, Pledged Notes and Pledged Note Liens, Pledged Interests, Flume No. 8 Facility Documents, GX II Security Documents, Warehouse Loans, Warehouse Facility Documents or Pledged Mortgage Loans;

(i) (i) all books, records, writings, data bases, information and other property relating to or evidencing any Pledged Shares, Pledged Notes and Pledged Note Liens, Pledged Interests, Flume No. 8 Facility Documents, GX II Security Documents, Warehouse Loans, Warehouse Facility Documents or Pledged Mortgage Loans, and (ii) all insurance policies, claims and/or insurance proceeds arising out of the loss, nonconformity or any interference with the use of, or any defect or infringement of rights in, or damage to, any of the foregoing, in each case if and to the extent evidencing or related to any Pledged Shares, Pledged Notes and Pledged Note Liens, Pledged Interests, Flume No. 8 Facility Documents, GX II Security Documents, Warehouse Loans, Warehouse Facility Documents or Pledged Mortgage Loans;

(j) to the extent not included in the foregoing, all Accounts, Chattel Paper, Commercial Tort Claims, Deposit Accounts, Documents, General Intangibles (including Payment Intangibles), Goods, Instruments, Investment Property, Letter-of-Credit Rights, Letters of Credit, Supporting Obligations, Money and all other personal assets and property of any kind or description, in each case if and to the extent related to any Pledged Shares, Pledged Notes and Pledged Note Liens, Pledged Interests, Flume No. 8 Facility Documents, GX II Security Documents, Warehouse Loans, Warehouse Facility Documents or Pledged Mortgage Loans;

(k) all Proceeds, products, offspring, rents, issues, profits and returns of and from, and all distributions on any of the foregoing;

(l) all MSR Collateral; and

(m) all Derivative Collateral.

Nothing herein shall release or otherwise impair any security interest granted under any of the other Specified Documents, each of which will remain in full force and effect in accordance with its terms.

Each of the Grantors hereby covenants and agrees, no later than the date hereof, to pledge, or as the case may be, to pledge in advance, all of its rights, titles and interests in, to and under the GX II Notes and the related GX II Security Documents to the Omnibus Agent.”

SECTION 2.3 Amendments to Schedule IV .

(a) Exhibit C to Schedule IV of the Omnibus Security Agreement is hereby amended by inserting the following: