Questions about the 5 speed transmission

[Centaurious]

Several months back I replaced my bad manual transmission with a good used transmission. I took the time to clean and inspect it inside and out, replace all seals and shifter bushings and reseal the top cover and the tail-shaft housing including installing the three brass plugs. When I transferred over my old transmission mount it seemed in good shape being firm and almost impossible to twist or flex. when I installed the driveshaft I didn't grease the splines as I thought it would be lubed by the transmission fluid.

I have noticed that the shifter is jacking up and to the right under acceleration as if the driveshaft is pushing the rear of the transmission up and sideways. If I go over railroad tracks it also causes the shift lever to jerk around as well. This has been happening since the replacement of the transmission and I don't recall it doing this before.

My other Explorer was automatic so if this was happening I would never have seen it going on.

What is the wisdom of the group? Problem? or "They all do that"

 

[2stroke]

There will be a certain amount of flex with any rubber mount, but the tranny mounts are pretty weak as well. They are acceptable for daily driving, but I've torn quite a few from heavy towing. I am actually going to a polyurethane mount for the engine and transmission in my 93 to remedy this. In my 94 b4000 I would say the shifter moves about an inch under heavy acceleration with a new rubber mount. It was noticeably worse when the old mount tore. I didn't know it at the time, but I got a bit of a clunk, which turned out to be the transmission hitting the body. They are pretty good transmissions, my only complaint is 1-3 are quite a bit too tall for gearing. I like a nice low first to get going.

 

[Chirko]

See mounting the gearbox. And, perhaps, the driveshaft is in a different position. It is advisable to do the label when removing the shaft from the transfer case. Mounts transmission for RWD and 4WD vehicles are different.

 

[RangerX]

You say you inspected the mount when you installed the trans, several months ago. It possibly could have failed since then. It is a 20+ year old part...

 

[Centaurious]

Yes, it is 2wd. I've had other manual transmission vehicles before but I don't recall the rear end having so much effect on the transmission. There were no changes to the overall length of the M5OD-R1 in the later years were there?