Product Description
- The 6L90 drum listing says the bearing and bushing come installed; the 6L80 drum listing does not say. Check one 6L80 drum on the shelf before launch (if no bearing, add 33693).
- 6L80 drum: 1 available, 24 on order. 104860K: 5 available (limits the kit to 5).
- SOS and website prices differ on two parts (A104554B $249.95 vs $199.95; 104860K $0.00 vs $19.95); the kit price uses cost, not either price.
- Shoot one photo of the packed kit with the drum.
Fits: 6L80, 6L90 · 2008-up
The job: Transmission out and apart to the 1-2-3-4 / 3-5-reverse drum.
Delayed or slipping reverse, often with a flare on the 2-3 shift and sometimes a fail-safe mode, can come from a crack in the 1-2-3-4 / 3-5-reverse clutch drum where it rides on the bearing next to the pump. It is a known weak spot on the 6L80 and 6L90, and the cure is a new drum. This kit is the drum plus the seals and retaining rings you need to move your pistons and clutches over.
What is in the kit
- 1-2-3-4 and 3-5-R drum D-ring kit (8 rings) – 6L80DRUMRINGKIT-L
- 1-2-3-4 clutch piston housing retaining ring kit – 104860K
Transmission (you choose):
- 6L80 (4.555 in. drum): 6L80 forward and direct 1-2-3-4 / 3-5-reverse drum, aftermarket – A104554A
- 6L90 (taller drum): 6L90 forward and direct 1-2-3-4 / 3-5-reverse drum, aftermarket, bearing and bushing installed – A104554B
Every part is also sold on its own under the number shown, so a lost or damaged piece is easy to replace.
How the job goes
- Remove the transmission and take it apart down to the 1-2-3-4 / 3-5-reverse drum.
- Air-check the old drum and watch the bearing seat for leakage to confirm the crack before you order.
- Move the pistons, springs and clutch packs to the new drum with the new D-rings from this kit.
- Install the 1-2-3-4 piston housing retaining ring from the kit and check that it sits fully in its groove.
- Check the 1-2-3-4 and 3-5-reverse clutch clearances. Selective snap rings are sold separately if yours are out of range.
- Reassemble and run the clutch relearn with a scan tool.
You will also need
A clutch spring compressor, feeler gauges for clutch clearance, possibly selective snap rings, and a scan tool for the relearn.
Before you buy
Confirm the crack with an air check first; a slipping reverse can also be a torn D-ring or a worn clutch pack. This kit fits 2008 and later units; 2006-2007 drums use a different 3-5-reverse inner seal.
Kit price saves at least $14.40 over buying the same parts one by one.
