This tool offers easy, damage- free installation of power steering pump pulleys. It works on 1988-'95 GM Quad 4 engines; 1990-'94 Chevrolet Lumina APV, Oldsmobile Silhouette, and Pontiac Trans Sport vehicles; 1990-'94 3.1L V-6 engines; 1994- newer 3100 GM V-6; 1999- newer 3400 GM V-6. Threads are 3/8-16" to fit pulley shaft threads.