excessive torque/ movement in rear differential.

[Burpee Carr]

20O2 Ranger, stopped, shift from R to D. Clunking sound in differential and excessive torque in rear end. Travel in rear U Joint is at least a couple of inches up and down with the shifts. Seems to be something catching and releasing to cause the sound and movement./ No broken leafs no broken U bolts just a lot of movement. Truck is a 4 wheel drive with a limited slip. Four wheel drive not engaged for the problem to appear./ Thanks in advance for any help!

 

[4x4junkie]

2002 Ranger. When I have the truck stopped and I shift it from R to D, there's a clunking sound in the differential and excessive torque in the rear end. The rear U Joint travels at least a couple of inches up and down with the shifts. It seems to be something catching and releasing to cause the sound and movement. I don't see any broken leafs, no broken U bolts, just a lot of movement. Truck is a 4 wheel drive with a limited slip. Four wheel drive does not need to be engaged for the problem to appear. Thanks in advance for any help!

FIFY


As for your truck, the pinion u-joint moving up & down might not be anything abnormal, it may be what is called "axle wrap" or "windup" of the leaf springs. As long as it isn't making any weird noises (gear whine, bearing rumble) and nothing's broken or loose (loose u-bolts, etc.), it's probably not something to be concerned about (my truck's u-joint also moves up & down if I go forward or backward quickly).

A couple things you still might check though are the u-joints themselves, and the slip-yoke spline on your rear driveshaft, which might need to be lubed (it sticking). This can cause a thump or clunk when you take off from a stop. A moly-based CV joint grease works well for the slip-yoke.

 

[Burpee Carr]

Thank you , Junkie. The movement is sudden with a loud clunk. I some how do not think it is normal. If it is possible I will post a brief video. All most looks like something is catching and releasing causing the sound and causing the rear end to jump. I do have an old GMC I will look under to see how much movement is there and compare the two. I was thinking it had to do with the limited slip on the Ranger. Had the back off the differential nothing broke and no metal in the fluid.

 

[PopRichie77]

Are the shocks good?
I may have misunderstood what you are talking about.

 

[RangerX]

If you have a supercab Ranger, maybe the carrier bearing is shot.

 

[PopRichie77]

Yes, if the flange is moving up and down or in and out and the nut is tight, the pinion bearing is bad.

 

[4x4junkie]

Thank you , Junkie. The movement is sudden with a loud clunk. I some how do not think it is normal. If it is possible I will post a brief video. All most looks like something is catching and releasing causing the sound and causing the rear end to jump. I do have an old GMC I will look under to see how much movement is there and compare the two. I was thinking it had to do with the limited slip on the Ranger. Had the back off the differential nothing broke and no metal in the fluid.

If that GMC is old enough that it has coil springs in the rear, you would be comparing apples to oranges.

Leaf spring windup is a normal phenomenon (for every action, there's a reaction). As the axle turns the wheels to propel the vehicle forwards, a twisting force is transferred from the axle housing to the leaf springs, causing them to twist.

This isn't to say you don't have a problem under there... I don't know, but what you describe (the pinion going up & down) isn't unusual. If the driveshaft slip-yoke is sticking however, that certainly can cause a clunk.

Yeah, a video with decent audio for the clunk sound would likely help.

 

[Burpee Carr]

PopRichie77, the shocks are old. I will replace with new if bad shocks can cause this condition. and it is an Extended Cab. The GMC is an 94 4X4 and has Leaf Springs. Haven't had a chance to compare yet as I need a helper, same with the video. Thanks to all for your responses. I am confident we will get it sorted out,. I will get back under there and check for a carrier bearing. I think that is like a steady bearing?

 

[PopRichie77]

Explain a little better what is happening. We have all given answers to different problems.

 

[Burpee Carr]

If I am looking under the back of the truck at the rear diff and my helper is in the truck with foot on brake. little bit of throttle shifting from Drive to Reverse. There is a lot of movement in the rear axle (torque) form the loading of the leaf spring. The movement is not smooth or quiet.The torquing has a hitch and a clunk in it during the transition.. I just don't think it is normal. it seems like something is catching and then releasing to make the clunk. It will sometimes make the clunk when driving at road speed of 50mph plus or minus. but not always. I will post a video on the weekend. May start with new shocks as they are needed anyway. I will see if that calms it down any. Please note I expect the differential to load up in one direction and then then the other when shifting Causing the rear to torque. The hitch and clunk is what I think is abnormal.

 

[PopRichie77]

Bad U-joint or excessive play in the rear between the ring and pinion gear, each will make a clunk noise.