random clunking in rear after towing a 5x8... 45mph +

So I towed a modestly heavy load for 800 miles, and now that the trailer is gone it makes a really annoying clunking while I drive at an average speed of 60. The best i can do is describe it as a rock in a clothes dryer, and seems to be coming from the gas tank area (sounds like its smacking the floor). I first thought it was the wind blowing smething around but there's nothing under there. Any ideas? I hope it isn't the diff, but I just changed the fluid before I left for the trip. Thanks.

Have you gone under the Jeep and check for anything that's loose?

don't take this the wrong way ... but is the hitch ball still in the receiver?

might be worth it to take a look inside the diff ... just in case.

Devilfrog said:

don't take this the wrong way ... but is the hitch ball still in the receiver?

might be worth it to take a look inside the diff ... just in case.

Click to expand...

Yup, hitch is out. I can't find anything loose just yet. Can't be a shock, cause its still doing it on smooth roads.

What could bounce around in a differential, and wouldn't/could it get caught in the gears and just destroy my jeep?

it was the rattling part, but then I just re-read and you said it sounded like something was hitting the floor ... which leads me to question the upper shock mounts. Could be a bar pin has let go ...

Devilfrog said:

it was the rattling part, but then I just re-read and you said it sounded like something was hitting the floor ... which leads me to question the upper shock mounts. Could be a bar pin has let go ...

Click to expand...

That actually seems very plausible. If it ain't that, ill crack open the diff and find out its probably that.