4L60E Heavy Duty Rebuild Kit with High Energy Clutches

This is a heavy duty master rebuild kit for the GM 4L60E four-speed automatic (RPO M30). It is listed for all 1997-2003 4L60E transmissions and the 2004-and-later 4L60E used in Chevrolet and GMC trucks, SUVs and vans. The kit replaces the stock friction material with high energy clutches, which hold up better than paper-thin stock frictions when the truck tows, carries weight or has more power than it left the factory with.

A 4L60E usually comes apart for one of a few reasons: a burned 3-4 clutch pack that slips or flares on the 3-4 shift, lost reverse from a cracked sun shell or worn input clutches, or a 2-4 band that has glazed. Whatever put it on the bench, a full overhaul means every seal, gasket and friction gets replaced at once so you are not tearing it back down in six months.

On the bench, soak the new frictions in clean ATF before assembly, check clutch pack clearance on each drum as you stack it, and inspect the sun shell, input drum and pump bushings while the unit is open. Hard parts like the sun shell, band and bushings should be judged on condition, since a fresh friction set will not fix a worn drum or cracked shell.

Confirm the transmission tag reads 4L60E (not a 4L65E or 4L70E, which use different drum components) before ordering. Weighs about 9.5 lb in the box. Backed by a 6-month supplier warranty.