LS1 LS2 LS3 LS4 LSX LSA LS6 LQ4 LQ9 Engines,or LS powered hot rod. LS Harmonic Balancer Install Tool. Fits all GM LS series engines 1997-current (Gen 3, 4, & 5). Easy Job, Tool threads into crankshaft and pushes the crankshaft pulley into position.