Gradual Oil Loss (With No Recognizable External Leakage)

CAUSE/REMEDY:
The transmission oil is being drawn into the engine via a defective diaphragm in the vacuum modulator or the delay upshift vacuum element of the control pressure cable.

1. Replace vacuum modulator and clean vacuum lines.
2. Replace control pressure cable with pneumatic element, check all secondary vacuum consumers in the vacuum system, ie: PSE pump, orthopedic seats, etc. Clean lines if necessary.