Symptoms:

  • Direct clutch failure
  • Delayed 3rd
  • Delayed Reverse
  • Code 87, 730, 756, 1811
  • No 3rd
  • No Reverse
  • Maximum line presssure
  • No 4th
  • 2nd Gear starts w/MIL on
  • TCC slip codes

Cause:

Wear at the direct clutch drum bore from the center support piston rings allows 3rd and Reverse clutch apply oil to exhaust.

Correction:

Sonnax direct drum sleeve kit allows the salvage of worn direct clutch drum bores, and restores the hydraulic integrity at the center support piston ring locations.

Warning:

Recommended tool kit 34838-TL is no longer in production. Check with your distributor for availability.

400, 4L80-E, 4L85-E

Direct Drum Sleeve Kit
Part No. 34838-01K

In 4L80-E units, part can be used in either early or late-model drums.


View Instructions Find a Distributor

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.

  • Sleeve
  • Spring Pin
  • 400, 4L80-E, 4L85-E Direct Drum Sleeve Kit 34838-01K
  • 400, 4L80-E, 4L85-E Direct Drum Sleeve Kit 34838-01K