I have a friend whose Mopar mechanical and automotive skills I have great respect for, insists that a driveshaft yoke shoved into a transmission bushing with too much clearance is the root cause of many unexplained intransigenet driveline vibration issues.
He recommends a new bushing which is too tight and honing it out to fit the specific yoke you are using. He suggests with the transmission out of gear to relieve stress on driveline, to attempt to move the yoke up and down. Any permitted movement is indication of potential problem.
I will forward this thread to him for comment.
Sounds good. Yes, although there really wasn't any play at all on the slip yoke, I am starting to think the tailshaft bushing is the culprit. Realistically, the transmission as a whole is kind of tired. It leaks a bit from somewhere on the left side after sitting overnight and has for a while. I add fluid when needed every 2 or 3 months. First gear (not in it long because it is so short) whines some.
All and all, I think it needs a freshen. Until I can, I'll just ride around and not be too harsh on it. Since the mentioned minor pulsating vibration is more evident in 4th/OD, I will just keep from using it as much as possible except on the highway (just in case it is something in that gear as well) I usually do that anyways.
