clunking noise while in reverse

[jimmy1979]

I have a 1991 ranger, 4x4, manual, 4.0 v6. When I put the truck in reverse and start moving I can hear and feel a "clunk" noise comming from underneath somewhere. When I move forward it happens again. Its almost like something moves in reverse and moves back again when I go forward.
It isn't instant, sometimes I am moving in either direction for a few seconds before it happens.
I put the truck on a lift and checked it out, I didnt find anything loose.
Any ideas?

 

[shane96ranger]

Check your radius arm bushings. My Explorer did the same thing.

 

[jimmy1979]

A guy at work today told me to check the engine mounts and the u-joints. Does this sound right?

I will check the radisu arm bushings as well, thanks Shane.

 

[shane96ranger]

It could be those, but I would say if the sound is a clunk from underneath, it's radius arm bushings. You should be able to replicate the sound by grabbing your radius arms and jerking them up and down. The ones on my Ranger are squeaking, and I can generate the sound by moving them around.

Also, a U-joint will generally make a "ping" sound in my experience, rather than a clunk because your driveline is hollow. The sound would be similar to tapping a piece of metal on a hollow metal pipe.

I don't have experience with Ranger motor mounts, but when my Mustang mounts were bad, I could rock the motor back and forth by hand. Plus my fan was rubbing on the shroud pretty bad when I hit the accelerator.


- you may want to look at the trans mounts as well if the radius arms aren't the culprit.