pinion bearing advice

[mccrob]

I've got a 5 speed m50d out of a 92 3.0.It whines in every gear but 4th.Ive been told this is the pinion bearing,the slave and master have been changed and the tranny has been out twice for that job ,it was once everything was back together that the new problem arose.how hard of a fix is the pinion bearing and how much for parts.I still don't completly understand the problem yet so advice would be highly appriceated,it's an old beater truck and this is the last thing stopping me from driving more than 20 miles from home,everything else has been fixed

 

[Taragon]

You can get 20 miles or more. Just shift into 4th as soon as you can, or as often as you can, and stay there.

Basically you need to replace the POCKET bearing (the pinion bearing is in the rear axle). Its the bearing that is found inside the rear of the input shaft, and spins on the nose of the mainshaft.

Replacing it in and M5OD isnt too hard, but does require a complete teardown. Which means the trans has to come out once again!

 

[MAKG]

It's hard to imagine how the pocket bearing could get trashed without buggering the mainshaft AND input shaft.

And the usual cause is oil starvation, which means this transmission is junk, if that's true.

You don't just tear this thing down, replace the (easy) pocket bearing, and put it back together. If you do that, it's quite unlikely to be satisfactory. What you do is inspect ALL the parts and replace what's bad. If too many things are bad, you throw it away and get a better one from the junkyard. Perhaps keeping the good parts if you want.