A/T - 125/200/200 4R/325 4L Late or No Upshift
TSB 86-16 (Apr)SUBJECT: THM 125/200/200 4R/325 4L
PROBLEM:
Late or no upshift on any check ball type governor.
CAUSE:
The check ball on the pressure side bounces itself a flat spot, resulting in enough leakage to cause the pressure loss. (see illustration)
SOLUTION:
Replace the ball or governor - 1967 & 1968 MX and some FMX valve body check balls are the same diameter.