X0202 4 2005-02-02 0000003982 Allis Chalmers Energy Inc. ALY 0001140824 HIDAYATALLAH MUNAWAR H 5075 WESTHEIMER, SUITE 890 HOUSTON TX 77056 1 1 1 0 Chairman and CEO Option to Purchase Common Stock 3.86 2005-02-02 4 A 0 600000 A 2015-02-02 Common Stock, par value $0.01 per share 600000 600000 D This option is exercisable (a) immediately with respect to 200,000 shares, (b) on February 2, 2006 with respect to an additional 200,000 shares, and (c) on February 2, 2007 with respect to the remaining 200,000 shares. Grant under employee stock option plan. /s/ Munawar H. Hidayatallah 2005-02-04