91 voyager AWD grinding problem

I have a 91 voyager AWD (4sp auto) with what I believe is a stripped spline in the front end. It drives forward okay under load, but freewheels on decelleration/manual downshifting with a crunching/course grinding sound (from front).

Same grinding sound from transaxel when in reverse. Driveshaft to rear diff spins, but van doesn't move. I can hear park pin rattling until driveshaft stops, and appears to lock in place when the driveshaft stops.

When in park the van will roll forward or backward, but not like it's in neutral.

I haven't jacked it up to learn more, but I believe the front end is doing nothing more than powering the rear driveshaft, and the rear diff in-line clutch doesn't lock in when the tranny is put in reverse.

This appears to be a less common problem, as I haven't located anything in the last two nights of searching.

Purchased sight-unseen. Body looks good and it's really quite shiny. The nearly new tires hold some value if this turns out to be non-economical for me.

Thanks in advance,
charles

Thank you for your help, that fixed it.

BTW, mine won't start once a day, no spark. I thought I knew something, as a pattern was forming (that works), but seems I was wrong. I now find removing one battery post for a couple seconds (key off) restores the spark and it works fine until the next time. It's not a fix, ...........

charles

Sorry I am missing something. What was the fix??

change drivers side front axle. Passenger side axle was changed two weeks before drivers side failure. Apparently common for the balls to fall out according to documentation included with new axle. Motor mounts are good so I don't know what to make of that..... maybe plymouths motor-mount tolerances aren't within their axle tolerances?

I haven't found the info I need, but it looks like they have some overly elaborate electric over vacuum system that's supposed to actually lock the rear driveshaft when the computer senses the vehicle may be in reverse). It doesn't seem right tho, as it makes no sense any engineer would create five pounds of problems to do something a solinoid or motor could accomplish. Of course maybe they had to find a way to computer control it, as the reverse switch simply couldn't handle such a simple task? I won't be driving it this winter.

charles