I recently bought a '99 Trooper running 285/75's with a T-bar crank to match the height of the rear with OME 919 springs. Not really sure how high, but IMO too high so dropped by at least 1.5". The point of this is the front has been way cranked for probably two years and about 30,000 - 45,000 miles.

When I bought the truck, the owner warned me of the clunk (he is pretty sure it is brake caliper), but my mechanic (who I have since come to realize is no where near as good as I thought he was) seemed to think it was no big deal. I have not driven the truck much, but the noise is not really getting worse. I do notice that there is more vibration obvious at slow speeds than I would have expected. Today, when moving at a walking pace or slower it felt like something was grabbing and releasing.

On the way home I took it to a parking lot and drove in tight circles with the window as the problem is most noticable when turning. I could neither hear nor feel anything, with the glaring exception of the loud pop (I could feel it through the floor) when, after doing forward circles for a while, I switched to doing backward circles.

So the loud pop happens when I change direction with the wheel at or close to full turn.

Can anyone shed some light on what this might be? The CV boots are not torn or show any unusual signs of wear. I know very little about the history of the truck besides the lift, as mentioned above (thank goodness Matt keeps records!).

Thanks for the help!
Bill

Well, it sounds like a CV joint is bad to me, but my truck is a 4x2 so.... My only experience with a similar situation was on a '90 Dodge Shadow, it would pop like that in a turn. Ended up having the shafts rebuilt.

Larry

My Trooper does the exact same thing, but I don't think it's the CV as I replaced it not long ago after damgaging on a trail ride. I think mine might be a loose bushing on top of shock mount. Not sure I plan to get is checked out soon. Let us know if you find out first.

I will be adding manual hubs in the next couple weeks. If that clears up the problem I will report back. I really hope it is not the CV's.

Could be a body mount ?

I don't have a complete answer yet, but thought I would post back. I removed the front sway bar and the noise is basically gone.

I really doubt it is a loose brake caliper, you'd feel it during braking, not during tight circles.

It could be the following:
Bad ball joint, either upper or lower
Bad tie rod end, there are 4 of them on my rodeo.
Front sway bar bushing - plausible, but unlikely.
Shock mount loose - plausible.

Do you have a limited slip differential in the rear? If the wrong gear oil and no LS oil additive, this can cause the differential plates to grab and make squealing noises during turns.

4-wheel drive not dissengaging? Far fetched, as you would definately notice it in its driving characteristics - it wouldn't want to turn at all on dry pavement.

I recommend that you jack up the truck's front end and get both wheels off the ground. With the ignitian unlocked, you can then manually move a wheel back and forth and feel if it doesn't move smoothly, or else have someone turn the steering wheel. This should allow you to determine which side is the problem if you feel popping or roughness. Then remove the wheels and start grabbing stuff and shaking it to see if it has any play in it, like the tie-rod ends. Inspect the rubber boots over the tie rod ends and ball joints. Squeeze them and look for tears. If torn, then they are suspect and should be replace anyway. If you replace one ball joint, then replace them all, upper and lower, driver's and passenger's side. Same thing with the tie rod ends. If you replace any of these, before you remove the old ones, make sure to count the nuber of threads visible and measure the length so you can install the new ends to nearly the same adjustment. The work isn't that hard, and you can rent a ball joint / tie rod press at Shucks Auto for $6 per day.

If you do end up replacing ball joints or tie rod ends, have the alignment checked ASAP.

Good luck

I had something very similar. A loud pop/clunk that I could feel through the floor board. Mine I only noticed while pulling in or backing out of a parking spot. Usually only after reversing the last direction with wheels cranked. I suspected it was the control arm bushings. After duct taping my video camera to the torsion bar I found out I was right. The LCA on the side I was hearing it from would move about 1/4" (looked like that much on the video at least) as soon as I hear the pop. I had to look at the video very closely several times to notice it since it was quick and not a lot of movement. Replacing the bushings got rid of the noise.

It sounds like an auto-engaging hub problem to me.