Rebuilding your first 4L60E out of a Chevy S10, Camaro or half-ton pickup and tempted to set the new bushings with a socket from the toolbox? That is how a fresh unit ends up back on the bench. This kit gives you twelve hardened steel drivers, each turned to a bushing outside diameter in the GM 700R4, 4L60, 4L60E and 4L65E, plus one knurled handle that threads into every driver. The blow centers on the bushing, so it travels straight down the bore instead of tipping.
Why bushings matter so much in a 4L60E
In this transmission a bushing is doing two jobs at once. It holds a drum or shaft on center, and it forms part of the oil circuit, because the clearance between bushing and shaft decides how much feed oil escapes before it reaches a clutch piston. GM's overhaul procedure lists bushings at the case, the pump body, the reverse input clutch housing, the input sun gear, the reaction carrier shaft and the reaction sun gear, each removed and installed with its own driver. Sonnax traces most burned 3-4 clutch packs on the 4L60/E to low line pressure and 3rd-gear oil leaks, and a cocked or oversized bushing is one of the ways that oil gets lost.
What a bad install looks like
- A bushing that sits higher on one side than the other after driving
- Bronze shaved off the edge and left in the bore, where it ends up in the valve body
- A collapsed bushing that grabs the shaft so it will not spin freely by hand
- A feed hole half covered because the bushing went in too far or rotated
- A repeat front seal leak or 3-4 slip within the first few thousand miles
Check before you start
Lay out the old bushings next to the new kit pieces and match each one before driving anything. Clean the bores, look for burrs left by removal, and dress them lightly if needed. Confirm the journals the bushings ride on are smooth, since a worn shaft will chew up a new bushing just as fast as the old one. If you are still deciding whether the unit needs a full rebuild, our S10 4L60E problems guide and Camaro 4L60E guide cover the failures that usually send these units to the bench.
Fitment
Sized for GM 700R4, 4L60, 4L60E and 4L65E case, pump and drum bushings. That includes the 1993-2013 Chevrolet and GMC trucks and SUVs, S10 and Sonoma, Blazer, Camaro and Corvette that used the 4L60E. It is not intended for the 4L80E, TH350, TH400 or non-GM units. Not sure what you have? Read the case ID tag or send us the year and VIN, and shop the matching soft and hard parts on our 4L60E collection page.
Install notes
- Bolt the case into a holding fixture and bench base so it sits square and does not rock while you strike.
- Thread the driver fully onto the handle before each use; a loose driver can cock under the first blow.
- Lubricate the bushing and bore with clean ATF and start it by hand until it stands straight.
- Use firm, even hits and check it is still square after the first few.
- Install new bushings alongside the clutch work. If the 3-4 pack was burned, the Raybestos 3-4 Z-Pak adds clutch capacity where this unit fails most.
- Check end play once the gear train is assembled; our 4L60E bench tools guide has the specs and gauges.
- Fill with Dexron VI and set the level hot.
Everything stores in a blow-molded case with a cut pocket for each driver, so a missing piece is obvious before the next job.
