In trying to solve the problem that this 84' 300D turbo upshifts through all 4 gears into drive at 20mph, the following process was followed:

1.) checked and adjusted throtle pressure cable
2.) checked vac supply to vac modulator
3.) checked modulator, itself
4.) removed valve body and checked throttle pressure valve for sticking or binding
5.) checked govenor assembly for sticking or binding
6.) checked trans. pump pressure (within spec.)


This 300D will also NOT downshift via kickdown switch.

1.) checked switch under pedal
2.) checked circut to solenoid
3.) checked solenoid itself

When you manually shift this trans., it has a nice firm shift. Doesn't slip and upshifts according to shifter position. In the process, the trans filter was changed and the contents of the pan inspected. There was virtually no material in the bottom of the pan and the fluid was clean and not scorched.

Anyone have any thoughts or suggestions?