I recently purchased a "project" 1985 300DT for $1500
. Today I removed all of the mechanical linkage on the accelerator/throttle system to clean and lube it. The improvements were as follows:
a) alot smoother throttle action.
b) cruise control holds speed within 2 mph now whereas it used to do some wierd stuff.
The biggest thing I found was that when I removed and reinstalled the linkage for the bowden cable I noticed that the mechanical mechanism that pulls the bowden cable was located on the "wrong" side of the mechanical contact point. It was in such a position as to never "pull" the bowden cable. After I relocated it the tranny shifts like it is supposed to. The problem that the tranny was showing prior to this was that it used to shift into high gear before 35 mph.