Symptoms:

  • Delayed engagement
  • No movement
  • Pump noise
  • Low line pressure

Cause:

The pump flow control canister and plunger valve wear, allowing the plunger valve to stick open and/or leakage to occur. The canister O-ring relaxes and pressure bleeds past it.

Correction:

Sonnax drop-in pump flow control valve kit includes a harder canister with more support for the plunger valve, which prevents sticking. The assembly also includes a case-hardened plunger valve with self-centering annular groves, a replacement spring and larger O-ring for improved sealing.
  • 5R55N, 5R55S, 5R55W Pump Flow Control Valve Kit 56200-03K
  • 5R55N, 5R55S, 5R55W Pump Flow Control Valve Kit 56200-03K