Just installed Duratracs (315/75R16) and Spidertrax 1.25" spacers on my '11 JKU. No lift, Mopar High Top Flares.

Was golden for the first 30 miles, shared between around town and highway, then all of the sudden developed a significant "rotational thud" out of nowhere - it's a loud "thud" type sound from the rear that speeds up in frequency as I pick up speed - interestingly i don't hear it so much going up hill, but very much down hill.

As I'm in the zone of the winter cluster-f happening right now, and don't have an indoor garage, wasn't sure if anyone had experience with this before I started pulling the wheels off in single digit weather.

Thanks in advance.

 

Is it possible that you have build-up of mud/ice/snow on the wheel area? Another alternative, you don't want to experience, is that your rear end gears are going out. Your description is rather close (except for that uphill/downhill part) to when mine did. If you're having some of this weather making the news lately, I'd say probably the former. :-)

 

The snow/ice build up makes total sense - except the issue started the day before the weather did...