Symptoms:

  • Planetary failure
  • Planetary wear

Cause:

Insufficient lube oil and/or excessive clearances.

Correction:

This kit offers replacement parts for rebuilding damaged rear planet assemblies and gives rebuilders the option of replacing only the worn components.

4L60, 4L60-E, 4L70-E, 4L70-E

Round Washer
Part No. 77731-04

4-Pinion rear planetary

View Instructions Find a Distributor

Sonnax round washer 77731-04 is a direct replacement for worn or damaged OE washers in four-pinion rear planetary assemblies in listed GM transmissions. The Sonnax washer is made from through-hardened steel to help eliminate needle roller thrust wear.

  • 4L60, 4L60-E, 4L70-E, 4L70-E Round Washer 77731-04