I have the same problem with my '82 300td, Ron. I suspect it's either a bad kickdown switch or bad kickdown solenoid on the transmission. I have an '82 300cd that kicks down just fine. One of these days I'll get tuit with regard to the wagon. First thing I'll check is the switch with an ohmmeter, but replacing the switch would be too easy...Murphy's law suggests the $70 solenoid.

Russ M