Allis-Chalmers Amends Terms of Tender Offers for Its Senior Notes

Allis-Chalmers Energy Inc. (NYSE: ALY) today announced certain amendments to the terms of its previously announced tender offers to purchase limited amounts of its 9.0% Senior Notes due 2014 (CUSIP Number 019645 AC 4) (the “9.0% Notes”) and its 8.5% Senior Notes due 2017 (CUSIP Number 019645 AE 0) (the “8.5% Notes,” and together with the 9.0% Notes, the “Notes”).

Pursuant to its Offer to Purchase dated May 20, 2009 (the “Offer to Purchase”), Allis-Chalmers commenced tender offers to purchase up to a maximum acceptance amount of $100,000,000 of the 9.0% Notes and up to a maximum acceptance amount of $25,000,000 of the 8.5% Notes, in each case at a purchase price determined in accordance with the procedures of a modified “Dutch Auction.”

Allis-Chalmers is amending the terms of the tender offers as follows:

• The 8.5% Maximum Acceptance Amount is increased from $25,000,000 to $50,000,000. Accordingly, Allis-Chalmers is offering to purchase up to $50,000,000 aggregate principal amount of its 8.5% Notes, upon the terms and subject to the conditions set forth in the Offer to Purchase and the related Letter of Transmittal, in each case as amended by this press release.
• The 9.0% Maximum Acceptance Amount is decreased from $100,000,000 to $75,000,000. Accordingly, Allis-Chalmers is offering to purchase only up to $75,000,000 aggregate principal amount of its 9.0% Notes, upon the terms and subject to the conditions set forth in the Offer to Purchase and the related Letter of Transmittal, in each case as amended by this press release.
• The Early Participation Date applicable to each of the tender offers is extended from 9:00 a.m., Eastern Time, on June 3, 2009 to 5:00 p.m., Eastern Time, on June 18, 2009. Consequently, holders who tender their Notes of either series prior to such extended time, and have their Notes accepted by Allis-Chalmers for purchase, will be entitled to the Total Consideration for such Notes, which will include the Early Participation Payment of $20.00 per $1,000 principal amount of Notes accepted for purchase.

The Withdrawal Date applicable to each of the tender offers will continue to be 9:00 a.m., Eastern Time, on Wednesday, June 3, 2009. Consequently, holders who have tendered and not withdrawn their Notes prior to that time are not entitled to withdraw their Notes, and similarly, holders of Notes who tender their Notes after the Withdrawal Date, but on or prior to the Expiration Date, may not withdraw their tendered Notes.

Each of the tender offers will continue to expire at 5:00 p.m., Eastern Time, on June 18, 2009, unless extended or earlier terminated by Allis-Chalmers.

The Tender Offers are conditioned upon the satisfaction or waiver of certain conditions, including Allis-Chalmers’ receipt of the funds necessary to complete the Tender Offers from its previously announced rights offering and convertible preferred stock sale, which are each subject to certain terms and conditions. Subject to applicable law, Allis-Chalmers may terminate the Tender Offers at any time before the Expiration Date in its sole discretion.

Allis-Chalmers has retained RBC Capital Markets Corporation to act as the dealer manager for the Tender Offers. Global Bondholder Services Corporation is the information agent and depositary for the Tender Offers. Questions regarding the Tender Offers should be directed to Mario Lewis at RBC Capital Markets Corporation at (212) 618-2204. Requests for documentation should be directed to Global Bondholder Services Corporation by calling toll-free (866) 470-3600 or (212) 430-3774 (for banks and brokers).

This press release does not constitute an offer to purchase, or the solicitation of an offer to sell, any securities, and there will be no purchase of any securities in any state in which such an offer, solicitation, or purchase would be unlawful prior to the registration of qualification of such securities under the securities laws of any such state. The Tender Offers are being made only by means of the Offer to Purchase and related documents. The Tender Offers are not being made to holders of Notes in any jurisdiction in which the making or acceptance thereof would not be in compliance with the securities, blue sky or other laws of such jurisdiction. In any jurisdiction in which the securities or blue sky laws require the Tender Offers to be made by a licensed broker or dealer, the Tender Offers will be deemed to be made on behalf of Allis-Chalmers by the dealer manager, or one or more registered brokers or dealers that are licensed under the laws of such jurisdiction.

About Allis-Chalmers

Allis-Chalmers Energy Inc. is a Houston-based multi-faceted oilfield services company. Allis-Chalmers provide services and equipment to oil and natural gas exploration and production companies, domestically primarily in Texas, Louisiana, New Mexico, Oklahoma, Arkansas, offshore in the Gulf of Mexico, and internationally, primarily in Argentina, Brazil and Mexico. Allis-Chalmers provides directional drilling services, casing and tubing services, underbalanced drilling, production and workover services with coiled tubing units, rental of drill pipe and blow-out prevention equipment, and international drilling and workover services.

Forward-Looking Statements

This press release contains forward-looking statements (within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934) regarding Allis-Chalmers’ business, financial condition, results of operations and prospects. Words such as expects, anticipates, intends, plans, believes, seeks, estimates and similar expressions or variations of such words are intended to identify forward-looking statements, but are not the exclusive means of identifying forward-looking statements in this press release.

Although forward-looking statements in this press release reflect the good faith judgment of Allis-Chalmers’ management, such statements can only be based on facts and factors that its management currently knows. Consequently, forward-looking statements are inherently subject to risks and uncertainties, and actual results and outcomes may differ materially from the results and outcomes discussed in the forward-looking statements. Factors that could cause or contribute to such differences in results and outcomes include, but are not limited to, demand for oil and natural gas drilling services in the areas and markets in which Allis-Chalmers operates, competition, obsolescence of products and services, the ability to obtain financing to support operations, environmental and other casualty risks, and the effect of government regulation.

Further information about the risks and uncertainties that may affect Allis-Chalmers’ business are set forth in Allis-Chalmers’ most recent filing on Form 10-K (including, without limitation, in the “Risk Factors” section) and in its other SEC filings and publicly available documents. Allis-Chalmers urge readers not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. Allis-Chalmers undertakes no obligation to revise or update any forward-looking statements in order to reflect any event or circumstance that may arise after the date of this press release.