intermittently transmission lock up

[mrboomers74]

last year i put a 96 ranger 4.0 and m50d tranny into my 90 b2. so far ive put about 5,000 miles, all went well till recently. new clutch, pressure plate, throw out, and pilot. it locks up in all gears, up shifting and coasting is when its at wost. i thought drive shaft was causing part of problem, now in thinking it was only half the problem. at times can smell burnt clutch. any ideas where to look. all fluids are clean and full. now that driveshaft is replaced it feels like its locking near flywheel/clutch. i really dont wanna pull tranny again. sometimes it acts up after about 20 miles, or 20 feet. it shifts fine and clutch feels great. pushing clutch frees it up till it locks again. thank in advance for any advice

 

[Uncle Gump]

I think it's the input shaft bearing that's know to weld itself together.

When you say "lock UP"... do you mean lock the drive wheels kinda lock up?

 

[mrboomers74]

I don't think the wheels are locking, never been any skidding or anything. More like it tries to stall the engine when it locks. I could be wrong. Whatever is happening I believe if I didn't hit the clutch fast enough it would stop dead.

 

[RonD]

The clutch disconnects the engine from transmission
Rear wheels are always connected to the transmission

So, yes it reads like a transmission issue, its possible the rear axle/differential is binding up
If you have a 4x4 you could disconnect rear drive shaft and drive in 4WD to see if it still does it
And rear axle issue would usually be accociated with a "whining" noise, which you don't mention

But transmission is more likely, input or output shaft bearing, as it effects all gears
If its an input shaft bearing it could also stall the engine in Neutral unless you pushed clutch pedal in

If you have a 4x4 you can use M5OD-R1 from a 1990-2011 4x4 4.0l Ranger or Mazda B4000
(2001 and up are M5OD-R1HD so you need the whole shifter and arm, its different that earlier)

If 2WD then 1990-1997 4.0l M5OD-R1, they have a speedometer cable hook up, which was gone in 1998 and up
Early 4x4s used transfer case for speedo cable