4L60E Master Rebuild Kit Less Steels, 2004-Up

This is a master rebuild kit for 2004-and-later GM 4L60E transmissions, sold under manufacturer part number W74004EC. It covers the soft parts you replace on every teardown: a full friction clutch module, the overhaul gasket set, O-rings, Teflon and metal sealing rings, lip seals and the bonded rubber components. It is a less-steels kit, so plan to reuse your steel plates if they are flat and not heat-blued, or buy steels separately.

The front pump seal in this kit is the wedge-type design used on later units. Pull your old pump seal and compare before you start reassembly, because early-style pumps take a different seal.

On the bench: tear down, clean and inspect drums, pistons and bushings, then soak the new frictions in clean ATF before building the forward, overrun, 3-4, coast and reverse input packs. Install new sealing rings on the input shaft and stator, set clutch clearances as you stack each pack, and finish with the pan gasket and case seals. A 2004-up 4L60E that came in slipping, flaring 2-3 or burning up the 3-4 pack is the typical job this kit is built for.