I have a weird "clunk" sound in my passenger side front when going over bumps and switching from reverse to drive.

It's not very loud, but it's annoying. It sounds like the front-end version of loose U-bolts. It's a hollow, clunk-y sound. It sounds like something is shifting, but for the life of me I can't find out what it is. So far I have checked:

Sway bar and end links - all tight, with brand new bushings
Tie rod and ends
Steering stabilizer
Track Bar
Engine mounts
Shock mounting hardware
Lug nuts
And I rocked the car back and forth - nothing is noticeable.

The sound only comes from the passenger side, and only when I'm driving at low speeds (<30 - over 30 and I can't hear anything). What could it be?

Edit: my neighbor just said it could be ball joint(s) ... I will grease them later today and check for play.

On a flat surface and with your parking brake on, climb under the Jeep, grab your driveshafts and give them a twist. There should be minimal, if any, play. Also apply vertical pressure to them... essentially "shake" the driveshaft. There should be no movement there either. I was having somewhat of a similar sound coming from what I thought was the rear. If I was on an incline/decline at a stoplight, when I let my foot off the brakes I would hear a clunk before hitting the gas. Turns out my front axle is shot. I had about 3/4" of play on my front drive shaft. I took the driveshaft out to hopefully prevent any further damage while I rebuild a Dana 30 HP to take its place, but I'm pretty sure my front passenger hub is crap now too and needs to be replaced. Could be related, could just be old and time to replace. Any way, I'd check them out.

New data:

The "clunk" is worst when accelerating from a stop, with the steering wheel turned hard left (e.g., when making a tight left turn at a stop sign). No clunk when accelerating to the right.

The passenger side does not clunk when braking, or when accelerating up a hill. I can ride over bumps with the brakes off, hear the clunk, then re-ride the same set of bumps with the brakes on - nothing. Ditto with going up hills - no clunk when accelerating up the hill over a bump, but I hear the clunk when coasting up the hill. No clunk when braking downhill, but I hear the clunk when I coast downhill over the bump.

Perhaps it's something with my brakes? Or, one of the ball joints when shifting under load?

Maybe a bad hub:

I had the "clunk... clunk, clunk, clunk" on my '89 XJ. A bad shimmy at highway speeds and especially when I turned to the right.

It turned out to be my Axle U-joints.

Lay down and give them a wiggle. If there is any play, they are bad and need replacement.

Of course, your Jeep may not be an '89... and since you never gave us the info, we may never know.

I had a similar issue today, but my driver side rear wheel was loose. I tightened up the lug nuts and now it's good.