Fits 1997-07 GM Gen III LS1 and Gen IV LS2 engines with 2004 & later two-piece thermostat (GM PN 12600172). This pump features a 3/4 ball/ball bearing and measures 6 from the block surface to hub. Pulley not included. Pulley #8898 is a universal design and manufactured from hard anodized billet aluminum. It will work with our LS water pump #8896 and most belt offsets found in GM Gen III and Gen IV small-block V8 engines. This pulley features a stock diameter and requires a 3/4 pilot shaft.