Thumping noise, front passenger side. Motor mount

Hi,
My 99 XJ with I6, 4X4 recently develop this annoying thumping noise. It happens when going over the bumper or riding on rough road surface. I checked all suspension and steering leakage, everything seems normal, no play or loosen connection. Could this be a motor mount? Will a failing Ujoint also make this noise.

Well, crawl under there with a bright light and a pry bar and try moving the engine mounts.

Did you check the ball joints on that side?

Did you check your shock mounts?

Hey, welcome to !

I don't know much about this except what I've experienced with my '98 XJ.
What does the thump seem to synchronize with, the road bumps, or wheel rotation?
IMPE, a failing u-joint is more of a rapid click/click the follows wheel rotation. If the thump is following road conditions then it may be the bushings on the shock absorbers or the track bar bushings.
just my .o2, dn

Thanks for all the replies, folks.
I have not checked the ball joint on that side, could someone tell me how to check it?
The noise is synchronized with the road bumps at the beginning. But it starts to get worse and can happens on rough surface.
The shock and shock mounts are tight as I recently replaced all shocks. I also check the trackbar bushing and it is tight as well.

Been traveling and not on checking for a few days. Check ball joints two ways. Lift the tire off the ground enough to get a long 2x4 or similar under freely the tire. Pry upwards while watching the ball joint in question. Even slight vertical movement in the ball joint indicates it's worn out. Check all four ball joints. You can also grab the elevated wheel at 12 & 6 to check for unusual movement although this often indicates that the uni hub bearings are worn.

hth, Doug

Check or just replace your transmission mount maybe. I had a thump over rough/washboard roads and it felt like it was coming from under my feet. Replaced the transmission mount and no more thumping.

The old mount was Really smashed down and clearly worn out lol.

Check your sway bar bushing..