Control Pressure Too Low
- Low transmission fluid level.
- Defective vacuum modulator assembly.
- Oil strainer blocked or restricted, gasket damaged or omitted.
- Oil pump gear clearance incorrect; gears damaged, worn or installed backwards; pump-to-case gasket out of position; defective pump body and/or cover.
- Valve body pressure regulator or boost valve stuck.
- Pressure regulator valve spring too weak.
- Internal leak in forward clutch circuit (pressure low in Drive range, normal in Neutral and Reverse); check pump oil seal rings and forward clutch seals.
- Internal leak in direct clutch circuit (pressure low in Reverse, normal in all other ranges); check direct clutch outer seal and 1-2 accumulator piston and ring for damage.
- Check ball missing from cored passages in case face.