Tool Required Machining Required
- 2nd Gear starts w/MIL on
- Code 87, 730, 756, 1811
- Delayed 3rd
- Delayed Reverse
- Direct clutch failure
- Maximum line presssure
- No 3rd
- No 4th
- No Reverse
- TCC slip codes
Wear at the direct clutch drum bore from the center support piston rings allows 3rd and reverse clutch apply oil to exhaust.
This new sleeve allows the salvage of worn direct clutch drum bores, and restores the hydraulic integrity at the center support piston ring locations.
Direct Drum Sleeve Kit
- Spring Pin
In 4L80-E units, part can be used in either early or late-model drums.
Wear at the direct clutch drum bore in GM 400, 4L80-E and 4L85-E units allows 3rd and Reverse apply oil to exhaust. This oil leakage can result in direct clutch failure, delayed or no 3rd/Reverse, slips in 3rd or no 4th gear, and the various slip codes noted above. Often the direct drum bore is worn beyond the ability for new seals to restore the hydraulic integrity.
Sonnax direct drum sleeve kit 34838-01K salvages worn direct clutch drum bores and restores the hydraulic integrity at the center support piston ring locations.
- Machining of the direct drum is required
- Sonnax sleeve installation tool 34838-TL is recommended, but not required.