• Band failure
  • Forward slip
  • Burnt Forward band


The OE forward band servo pin was designed with excess travel needed to apply the band. This travel can affect band apply, and the energy from pin travel can cause the band to break over time.


Replace the OE forward servo band pin with Sonnax extended length forward servo band pin kit to position the pin closer to the band apply position.

4T60-E, 4T65-E

Extended Length Forward Band Servo Pin Kit
Part No. 84571-01K

View Instructions Find a Distributor

Vehicles with GM 4T60-E and 4T65-E transmissions may exhibit case wear at the forward band servo pin bore. The OE pin is also shorter than necessary. These issues both may lead to slipping of the forward band. The longer throw of the shorter OE pin may lead to a broken forward band. Sonnax extended length forward band servo pin kit 84571-01K is designed to address both of the issues.

  • Increased length optimizes forward band apply
  • PTFE seals on both sealing diameters
  • Servo Pin
  • Pin Seals (4) PTFE, 2 Extra
  • 4T60-E, 4T65-E Extended Length Forward Band Servo Pin Kit 84571-01K