4L60E/4L65E Super Master Rebuild Kit w/Steels & Pistons 2004-Up

This is the W74008GAP super master kit for the late GM 4L60E and 4L65E, and the detail that sets it apart is the 12-piece bushing kit packed in with the clutches. If your 2004-or-newer Silverado 1500, Sierra 1500, Tahoe, Yukon, Suburban, Express or Savana van is slipping out of 3rd, flaring into 4th, or throwing a converter clutch code, a worn bushing is often part of the story, and this kit lets you replace the bushings, frictions, steels, pistons and band in the same teardown.

What this kit does in a late 4L60E

Inside the 4L60E, sealing rings on the input shaft and stator shaft feed oil to the rotating clutch drums, and the bushings keep those shafts centered so the rings can seal. Once a bushing wears, the shaft walks off center, the rings leak, and clutch apply pressure bleeds away. The pack that suffers first is usually the 3-4 clutch, which is why a burned 3-4 pack and a sloppy pump or input bushing are so often found together. The W74008GAP covers both sides of that failure: a Raybestos friction module with high-energy 3-4 plates, a 22-piece steel module, a 3-piece molded piston set, a Borg Warner 2-1/4 inch band, the 12 bushings, a thrust washer kit, the overhaul gasket and seal set, and a deep pan filter.

Symptoms this kit addresses

• Slip or flare on the 2-3 or 3-4 shift, worse when hot or towing.
• No 3rd or 4th after the 3-4 clutch pack burns.
• Converter clutch slip codes such as P0741, which can come from worn bushings and leaking rings starving converter apply oil as well as from a worn valve body.
• Soft or harsh shifts with P0748 logged. Rule out the pressure control solenoid and its wiring before you blame the hard parts.
• Fluid that is dark, burnt-smelling and full of friction debris.

Diagnosis before you buy

Codes and fluid tell you which direction to go. A P0741 or P0748 with clean fluid usually points at the valve body or solenoids, not the clutches. Sonnax and Transmission Digest both describe vacuum testing the valve body to find worn bores before you spend money, and our 4L60E valve body walkthrough covers it. If the pan holds clutch material and the truck slips in gear, the unit needs this kit. For the full list of failure patterns and what each costs to fix, read 4L60E common problems and fixes.

Fitment

The listing covers the GM 4L60E and 4L65E from 2004 and up, in Silverado and Sierra 1500, Tahoe, Yukon, Suburban, Express and Savana vans, and Cadillac Escalade. Some later Escalades and full-size trucks moved to a six-speed, so check the RPO sticker in the glovebox and make sure the transmission code is for a 4L60E or 4L65E. Units from 1993-2003 take a different kit. If you want us to confirm, send the year and VIN. All of our parts for this transmission are on the 4L60E shop page.

Install notes

• Measure each bushing bore before pressing in the new bushings, and replace the drum or housing if the bore itself is worn, not only the bushing.
• Air-check every clutch circuit and the servo after assembly, before the valve body goes on.
• On units built after March 2007, GM revised the reaction carrier, bearing and shaft. Transmission Digest notes these must stay a matched set, so do not mix early and late pieces when you replace gear train parts.
• Set 3-4 clutch clearance with the selective plate, pre-soak frictions in Dexron VI ATF, and fill with Dexron VI.
• Fit the wide band only to a new or resurfaced drum.
• If the valve body tested worn, an updated 4L60E valve body saves the new clutches from low line pressure. A fresh 5-piece solenoid kit is cheap insurance while the pan is down.
• Flush the cooler and lines before the first fill.

What does the 12-piece bushing kit cover?

It replaces the bushings that center the rotating shafts and drums in the 4L60E. Worn bushings let sealing rings leak and starve clutches of apply pressure, so renewing them protects the new frictions in this kit.

Is this the same kit as the other 2004-up super master kit you list?

It is the same 2004-up super master configuration. This listing carries manufacturer part number W74008GAP and specifically lists the 12-piece bushing kit and overhaul gasket and seal kit in the contents.

Will it fit an Express 1500 or Savana van?

Express and Savana vans with the 2004-up 4L60E or 4L65E are on the listed fitment. Heavier-duty vans often used a different transmission, so confirm the RPO code or send us the VIN.

Do I need special tools for the bushings?

You need a bushing driver set and a way to measure bore size. Pressing bushings in crooked or into a worn bore will cause the same leak you are trying to fix. Our bench tools guide lists what to have on hand.

What fluid does the rebuilt unit take?

Dexron VI ATF, both for soaking the new frictions and for the fill. Check the level hot with the engine running.

• 4L60E Valve Body Rebuild: A Bench Walkthrough
• 4L60E Common Problems, Symptoms, and What to Actually Do About Them
• 4L60E Rebuild: The Bench Tools You Actually Need
• 4L60E Shift Solenoid Symptoms, Testing and Replacement