front end clunk, please help!

First off, 92 xj, 4.0, auto, 4x4. I just put new pads and rotors on and about 30 miles later my front end started making a clunk consant to whatever speed im going. Against my better judgement I drove it about 40 miles to and back from a camping area. I didnt really notice it on the highway, but as soon as Im going under 50 I hear and also feel it in the floor a little bit . As I was doing the brakes I checked out the u-joints and the hubs, everything seemed fine, old but still in pretty good shape. As soon as I got back from camping me and my buddy took a look at it. We have both assumed that it is in the differential, so I took the cover off to see if it was something obvious like a chipped or broken tooth on any of the gears, and didnt see anything strange, it all looked pretty good, I pried on the ring gear lightly, and it seemed fine ( I thought the ring gear bolts had backed themselves out). So maybe the front driveshaft? No, took it out and the clunk is still there. As of right now im stuck, and with no job money is tight and I dont want to take it to a shop, or end up replacing a bunch of the wrong parts myself. Can anyone help me out here?

Check and make sure your shocks are tight at the top and that the bushings in the bottom of the shocks where the bar pins go through are not wore out.

If they are good check the upper and lower control arm bushings, its usually the ones on the passenger side that go first due to oil leaking on them from the filter adaptor.

If they check out good, jack each front wheel off of the ground and check the ball joints by grabbing the tire at the top and bottom and pushing/pulling at the top, if there is slack its either the ball joints or the wheel bearings.

That would be the front axle u joints maybe ?

Low Range said:

That would be the front axle u joints maybe ?

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Don't think so, they will click like a card in a bike wheel.

I agree with checking the control arms, I had a lower that was loose.

i dont think a constant clunk would be coming from the CA's unless youre driving down a loggin road, lol

I'd go back to your brakes, and make sure you have everything perfect, and the pistons are working correctly on your calipers, did you regrease them when u had it out?!

Does it go away when u break? Get worse?

Is it a clunk like a hammer smacking the bottom of your jeep? Or can you possibly give a deeper description?!

my clunking was a borken transmission mount. The rubber seperated from the metal casing and allowed the tranny to swing back and forth banging into the channel and causing what I thought was a worn control arm bushing.

might also check the motor mounts

If you took the axle nuts off the ends of the axleshafts, when you put them back on did you torque them to 175 foot lbs? If they are loose the unit bearing will sh1t itself in short order.

Autozone has sold me a defective rotor!!!! The stud holes are a little too big and it was wobbling on the hub. Last part I buy from autozone

have you replaced it and noticed the clunking gone? Cuz I don't think that's your problem. Unless you are being sarcastic.

I am not being sarcastic, that was the problem

The holes in the disc are 16 mm (if I remember correctly) the studs are 1/2" (again If I remember correctly) and are 16 mm for the last 10 mm or so (maybe a little less). Except on many after market hubs, the stud is 1/2" all the way to the base. The disc centers in the middle and the lug nuts hold the disc tight against the hub. Likely tight enough so it doesn't shift and slap against the studs.
I'm wondering if there isn't a bushing kit for the difference in the stud size and the holes in the disc.
Of course if the lug nuts are loose enough to allow the disc to shift, they are likely too loose.
Is it possible you forgot the anti rattle springs. Without them the pads often sound like a tin can with a lug nut inside. Every bump causes the pads to clank.
Disregard, I just checked the book and they changed the pads in 90, to the type with the clamp on the back instead of the anti rattle spring.

I've had loose lugnuts sound like you describe.