A/T - Harsh 1-2 Upshift or Slide Bump 1-2 Upshift

TSB 88-25 (June)

SUBJECT: FORD AOD

PROBLEM: Harsh 1-2 upshift, or slide bump 1-2 upshift

CAUSE:
May be caused by improper intermediate clutch pack clearance

Many technicians have experienced this condition, and blamed it on the friction plate manufacturer. This is not where the fault lies; in fact, the friction plates may be of a better quality than the original friction plates.

If intermediate clutch pack clearance is not checked on AOD transmissions, the intermediate return spring assembly in the pump may drag the clutch pack and glaze the frictions in reverse and low gears.

This can happen before the vehicle is road-tested, and cannot be fixed without removing the glaze from the friction plates.




Intermediate clutch pack clearance can be checked with a tool, or through a small hole in the case after the front pump has been installed. (See Figure)

Proper intermediate clutch pack clearance is:

.030"-.042"