Symptoms:

  • Worn accumulator piston pin bore
  • Soft & inconsistent shift feel
  • 1-2 Flare
  • 2-3 Flare
  • 2nd Slip
  • 3rd Slip
  • 2nd Clutch burned (GM)
  • 3rd Clutch burned
  • No 2nd
  • No 3rd

Cause:

Excess wear at accumulator piston pin bore allows circuit pressure to escape.

Correction:

Recover hydraulic control and renew shift feel and performance by reconditioning the pin bore and installing Sonnax oversized accumulator pin.

4T60, 4T60-E

Oversized Accumulator Pin
Part No. 84573-01K

Fits 1-2 and 2-3 accumulator locations only

Package Quantity: 4


View Instructions Find a Distributor

GM 4T60 and 4T60-E units commonly display negative shift characteristics that can be traced to excess wear at the 1-2 and 2-3 accumulator piston pin bores. Slipping, flares, and soft or inconsistent shifts often result, followed by burnt 2nd and 3rd clutches. Extreme cases will cause a loss of 2nd, 3rd and/or 4th gears. Restore hydraulic control and banish sloppy shifting by reconditioning the pin bore and installing Sonnax oversized accumulator pin 84573-01K.

  • Salvages accumulator pistons
  • Oversized pin creates tight hydraulic seal with OE piston
  • Starter kit 84573-02K includes reamer for boring piston pin bore
  • 4T60, 4T60-E Oversized Accumulator Pin 84573-01K
  • 4T60, 4T60-E Oversized Accumulator Pin 84573-01K