I have a issue on my 1987 4WD truck, most of the time it absolutely refuses to go from the 3rd gear to the 2nd when downshifting. I don't notice any difference with how long I've been driving, or how much gear shifting I have done during the drive. Most of the time 2nd gear just refuses to go in if I try to downshift from 3rd, but I can go to 1st gear from 3rd just fine, then instantly to 2nd. Any ideas on the cause?
I'm confused: you can't go from 3 to 2, but 1-3-2 is fine? Are you rev matching at all? Does it grind? A tired synchro would be my first guess if upshift 1-2 is fine but downshift 3-2 isn't fine without trying to rev match a bit.
The synchro is worn, and/or the clutch isn’t disengaging fully. The clutch could need adjusted, or the pilot bearing for the input shaft to the transmission may be wearing and letting the clutch hang down a bit, and rub on the flywheel.
