FIFTH AMENDMENT TO RESTATED LOAN AGREEMENT AND WAIVER

Exhibit 10.1

FIFTH AMENDMENT TO RESTATED LOAN AGREEMENT AND WAIVER

This Fifth Amendment to Restated Loan Agreement and Waiver (this “Amendment”) dated as of October 17, 2009, is made among GMX RESOURCES INC., an Oklahoma corporation (the “Borrower”), the BANKS (as defined below), CAPITAL ONE, NATIONAL ASSOCIATION, a national banking association, as administrative agent, arranger and bookrunner, for the Banks (and individually as a Bank), UNION BANK, N.A. (formerly known as Union Bank of California, N.A.), as syndication agent (and individually as a Bank), BNP PARIBAS, as co-documentation agent (and individually as a Bank), and COMPASS BANK, as co-documentation agent (and individually as a Bank), who agree as follows:

RECITALS

A. This Amendment pertains to that certain Third Amended and Restated Loan Agreement dated effective as of June 12, 2008, among the Borrower, the Agent and the Banks, as amended by the First Amendment dated as of October 29, 2008, the Second Amendment dated as of November 12, 2008, the Third Amendment dated as of February 26, 2009 (but effective as of December 31, 2008), and the Fourth Amendment dated as of June 3, 2009 (as amended, the “Loan Agreement”). As used in this Amendment, capitalized terms used herein without definition herein shall have the meanings provided in the Loan Agreement.

B. The Borrower, the Agent and the Banks desire to amend the Loan Agreement to permit the formation of a joint venture for the Borrower’s and Endeavor’s natural gas gathering business and assets, including the release of the Secured Parties’ liens on such assets, to reduce the Borrowing Base effective upon the creation, if any, of such joint venture, and to provide for other matters pertinent to the Loan.

C. The Borrower has requested a waiver of a financial covenant requirement for the period from August 1, 2009, through October 30, 2009. The Agent and the Banks are willing to accept the Borrower’s request on the terms and conditions set forth below.

D. The Borrower, the Agent and the Bank further desire to amend the Loan Agreement to permit the Borrower’s issuance of senior unsecured convertible notes, to permit the Borrower to pay in full all the outstanding Qualified Subordinated Debt, and to delete the net worth financial covenant.

AGREEMENT

NOW, THEREFORE, in consideration of the terms and conditions contained herein, and the loans and extensions of credit heretofore, now or hereafter made to the Borrower by the Banks, the parties hereto hereby agree as follows:

ARTICLE 1.

AMENDMENT AND AGREEMENT (KINDER)

1.1 The Borrower, the Agent and the Banks hereby agree that, upon the effectiveness of this Amendment and the closing of the Kinder Transaction (as defined in Paragraph 1.2 below), the Borrowing Base on such date shall be one hundred forty million ($140,000,000.00) dollars, and at this time there is no Periodic Reduction in effect, all subject to future change in accordance with the terms of the Loan Agreement. Furthermore, Section 1.2 of the Loan Agreement is amended to amend the definition of “Borrowing Base”, and further Subsection 5.2(c) of the Loan Agreement also is amended (both as previously amended by the Fourth Amendment dated as of June 3, 2009), together to provide that the effective date of the next scheduled redetermination of the Borrowing Base in 2009 shall be October 30, 2009 (instead of September 1).

1.2 The Borrower has requested the consent of the Agent and the Banks to a proposed transaction (collectively, the “ Kinder Transaction ”) involving the formation of a joint venture, Endeavor Gathering LLC, a Delaware limited liability company (“ Endeavor JV ”), by the Borrower and Kinder Morgan Endeavor LLC (“ Kinder Morgan ”) as its two members, and the contribution by the Borrower and Endeavor to Endeavor JV of materially all of the assets relating to their natural gas gathering business on the terms described in writing by the Borrower to the Agent and the Banks. Following such contribution, the Borrower will sell to Kinder Morgan a forty percent (40%) interest in Endeavor JV (after giving effect to certain preferential distribution rights in favor of Kinder Morgan in the Endeavor JV Agreement) for a purchase price of thirty six million ($36,000,000.00) dollars. The Borrower has requested the Agent and the Banks to release the assets being contributed to Endeavor JV from the Liens of the Collateral Documents. The “ Endeavor JV Closing Date ” shall mean the date the Kinder Transaction closes. The Agent and the Banks hereby consent to the Kinder Transaction under Sections 6.8, 6.14 and 6.16 of the Loan Agreement, on the terms provided in this Amendment, provided that the Endeavor JV Closing Date occurs no later than November 13, 2009. The Banks on behalf of the Secured Parties hereby agree to release (on the Endeavor JV Closing Date) the Collateral to be contributed to Endeavor JV, consisting of all of the assets relating to the Borrower’s and Endeavor’s natural gas gathering business, including without limitation pipelines, compression and related equipment, inventory, contracts and contract rights (including, without limitation, Endeavor’s right to retain a 2% marketing fee in connection with certain natural gas acquired by Endeavor from Borrower), capital and operating leases, undivided ownership interests in lands used as compressor sites, undivided interests in the Borrower’s co-tenancy properties used for pipeline operations, easements, and implied easement rights under oil and gas leases. The Banks on behalf of the Secured Parties further agree to the Agent entering into a subordination and non-disturbance agreement with Endeavor JV pertaining to all acreage in Harrison and Panola Counties, Texas, which is dedicated by the Borrower to Endeavor JV under the Gas Gathering Agreement. These consents shall not be a precedent for any subsequent requested waiver of (or consent under) these or any other covenants or other provisions of the Loan Agreement.

1.3 The Borrower shall use at least thirty six million ($36,000,000.00) dollars of the proceeds of the Kinder Transaction solely to pay the Indebtedness.

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1.4 Section 1.2 of the Loan Agreement is amended to add the following new definitions, each inserted in their respective proper alphabetical place, each to read in its respective entirety as follows:

“Consent by Other JV Member” shall mean the Consent and Acknowledgment by Member (Pledged Membership Interest) by Kinder Morgan Endeavor LLC.

“Endeavor JV” shall mean Endeavor Gathering LLC, a Delaware limited liability company, owned by the Borrower and Kinder Morgan Endeavor LLC (or its permitted successors and assigns).

“Endeavor JV Agreement” shall mean the Amended and Restated Limited Liability Company Agreement of Endeavor JV, dated as of the Endeavor JV Closing Date, as amended in accordance with this Agreement.

“Endeavor JV Closing Date” shall mean the date the Kinder Transaction closes.

“Gas Gathering Agreement” shall mean the Gas Gathering Agreement among Endeavor JV, Borrower and Endeavor, dated as of the Endeavor JV Closing Date, as amended in accordance with this Agreement.

“Joint Use Agreement” shall mean the Joint Use Agreement between Borrower and Endeavor JV, dated as of the Endeavor JV Closing Date, as amended in accordance with this Agreement.

“Kinder Transaction” shall mean the transaction described in the Fifth Amendment in this Agreement.

“Management Services Agreement” shall mean the Management Services Agreement between Endeavor JV and Borrower, dated as of the Endeavor JV Closing Date, as amended in accordance with this Agreement.

“Pipeline Operating Agreement” shall mean the Pipeline Operating Agreement between Endeavor and Endeavor JV, dated as of the Endeavor JV Closing Date, as amended in accordance with this Agreement.

1.5 Effective as of the Endeavor JV Closing Date, Section 3.1(a) of the Loan Agreement is amended to delete the phrase “its gas gathering system” and substitute (in the same place) the words “its assets” item (vi), and to add the following new clause (xii), such new clause (xii) to read in its entirety as follows:

(xii) Security Agreement executed by the Borrower, granting a first priority security interest in the Borrower’s ownership interest in Endeavor JV.

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1.6 Effective as of the Endeavor JV Closing Date, Section 4.16 of the Loan Agreement is amended to amend and restate Subsections (c) and (d), each to read in their entirety as follows:

(c) The Borrower’s natural gas production from substantially all of the wells operated by the Borrower located on acreage in Harrison and Panola Counties, Texas, is dedicated to Endeavor JV under the Gas Gathering Agreement. Otherwise, none of the Collateral is subject to any calls on production of hydrocarbons or any gathering or transportation dedications or commitments of any kind.

(d) Endeavor JV has good and marketable title to the gas gathering system servicing the Collateral in Harrison and Panola counties, Texas.

1.7 Effective as of the Endeavor JV Closing Date, Section 4.19 of the Loan Agreement is hereby amended by adding the following new Subsection (c), to read in its entirety as follows:

(c) The Borrower has provided to the Agent true, accurate and complete copies of the organizational documents (including the Endeavor JV Agreement) of Endeavor JV, and of the Gas Gathering Agreement, the Management Services Agreement, the Pipeline Operating Agreement, the Joint Use Agreement and the Purchase Agreement between Borrower and Kinder Morgan Endeavor LLC relating to Endeavor JV (including all amendments of any of the foregoing).

1.8 Effective as of the Endeavor JV Closing Date, Section 4.20 of the Loan Agreement is hereby amended to delete the phrase “and as to the gathering system Endeavor,” in Subsection (b), and further to add the following new Subsection (c), to read in its entirety as follows:

(c) Endeavor JV does not have an ownership (direct or beneficial) interest in any Person.

1.9 Effective as of the Endeavor JV Closing Date, Subsections 5.2(a) and (b) are each amended to add the following new sentence at the end of each Subsection, such sentence to read in its entirety as follows:

The consolidated financial statements of the Borrower shall include a consolidating schedule breaking out the financial results of Endeavor JV.

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1.10 Effective as of the Endeavor JV Closing Date, Section 5.11 of the Loan Agreement is hereby amended to add the following new Subsections (n) and (o), to read in its entirety as follows:

(n) The Borrower shall promptly furnish the Agent with copies of each notice of default, arbitration notice, or dispute notice sent or received by the Borrower under or pertaining to the Endeavor JV Agreement, the Gas Gathering Agreement, the Pipeline Operating Agreement, the Management Services Agreement or the Joint Use Agreement, and of each amendment, modification or waiver (retroactive or prospective) pertaining to the Endeavor JV Agreement, the Gas Gathering Agreement, the Pipeline Operating Agreement, the Management Services Agreement or the Joint Use Agreement or any new agreement pertaining to any of the foregoing.

(o) The Borrower shall promptly notify the Agent of the occurrence of any delinquency by a member under the Endeavor JV Agreement in making any Capital Contribution (as defined therein) to Endeavor JV as required pursuant to the Endeavor JV Agreement.

1.11 Effective as of the Endeavor JV Closing Date, Section 5.15 of the Loan Agreement is hereby amended to add the following new Subsection (f) to read in its entirety as follows:

(f) The calculations of EBITDA for purposes of the financial covenants in this Section 5.15 shall include cash distributions to Borrower from Endeavor JV. However, for the avoidance of doubt, the calculations of EBITDA for purposes of the financial covenants in this Section 5.15 shall not include Borrower’s proportionate share of the net income of Endeavor JV (even if Borrower otherwise includes such proportionate share in its income statement).

1.12 Effective as of the Endeavor JV Closing Date, Section 6.1 of the Loan Agreement is hereby amended to add the following new Subsection (j), to read in its entirety as follows:

(j) Debt under the Guaranty Agreement by the Borrower in favor of Endeavor JV, guaranteeing (only) the obligations of Endeavor under the Gas Gathering Agreement, the Pipeline Operating Agreement and the Assignment of Contract Rights among Endeavor JV, Endeavor and Borrower, dated as of the Endeavor JV Closing Date.

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1.13 Effective as of the Endeavor JV Closing Date, Section 6.3 of the Loan Agreement is hereby amended to add the following new Subsection (i), to read in its entirety as follows:

The Borrower’s ownership of equity interest in Endeavor JV, provided that the Borrower shall not make further capital contributions or investments (debt or equity) of any type in Endeavor JV after its formation and initial capitalization (as permitted by the Fifth Amendment to this Agreement), except in an amount not to exceed two million five hundred thousand ($2,500,000.00) dollars during any consecutive twelve month period.

1.14 Effective as of the Endeavor JV Closing Date, Section 6.15 of the Loan Agreement is hereby amended and restated, to read in its entirety as follows:

Section 6.15 Subsidiaries . The Borrower will not allow or suffer any changes to be made in the ownership structure of each Subsidiary, and shall not own and control directly or indirectly less than one hundred (100%) percent of the ownership and voting rights in each Subsidiary other than Endeavor JV. The Borrower will not create, incur, assume or permit to exist any Lien on its equity interest in any Subsidiary, other than in favor of the Agent (and a second Lien in favor of Subordinated Holder).

1.15 Effective as of the Endeavor JV Closing Date, Section 6.16 of the Loan Agreement is hereby amended to add the following new sentence at the end of such section, to read in its entirety as follows:

This Section 6.16 shall not apply to Endeavor JV.

1.16 Effective as of the Endeavor JV Closing Date, Article 6 of the Loan Agreement is hereby amended to add the following new Sections 6.18, 6.19 and 6.20, to read in their entirety as follows:

Section 6.18 Endeavor JV Debt . The Borrower will not allow or suffer Endeavor JV to incur, create, assume or in any manner become or be liable in respect of any Debt direct or contingent, except for:

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Section 6.19 Endeavor JV Liens . The Borrower will not allow or suffer Endeavor JV to create, incur, assume or permit to exist any Liens on any of its property now owned or hereafter acquired, except for:

Section 6.20 Endeavor JV .

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1.17 Effective as of the Endeavor JV Closing Date, Section 8.1 of the Loan Agreement is hereby amended to add the following new Subsection (q), to read in its entirety as follows:

ARTICLE 2.

WAIVER

2.1 (a) The Borrower has advised the Agent and the Banks that, notwithstanding the provisions of Subsection 5.15(e) of the Loan Agreement requiring a ratio of Total Debt to

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