Just had brake work done ... ever since, my Cherokee Grand Laredo has a slight lurch to the right whenever I take my foot off the accelerator at highway speeds. and then it lurches back to the left when I step on the gas. It's not much of a lurch, but it seems like I'm driving in snow ... except that the "drift" is abrupt and always in those predictable directions. This did not come on gradually. I just put new tires on it a few weeks ago, and it was handling so well that I looked down and caught myself doing 85 on the freeway. After the brake work ... anything over 50 feels like it's on snow. Feels like the rear end ... control arm. perhaps? Did the suspension hanging while it was on the loft for the brake job exacerbate a wear problem? Just noticed it on the way into work this morning. First highway use since the brake work. Doesn't feel like a brake rubbing ... rear feels loose, like it's slipping on snow, but only when removing foot from accelerator or stepping back on the gas.
Thoughts on where to look first?

 

Okay, I'm going to say worn rear lower control arm bushings. On my 97 ZJ, I had this problem to the extreme when one of my lower control arm mounts broke out of the frame! One side of the axle was moving back and forth with power changes and changing the thrust angle.

 

Dave was spot on.

Worn bushing. The lower control arm was worn, though, so replacing the bushing was not going to be a workable long-term solution. Since the entire control arm assembly is < $100, though, and is easy to swap out, not a big deal. Replaced both lower control arms, as the one on the other side was holding, but showing signs of wear and had a lot of rust.

Just in case someone else with similar symptoms does a search and finds this thread ...

The Jeep was consistently twitching to the right when I took my foot off the gas, and back to the left when I applied throttle. The left side lower control arm bushing was the culprit, allowing a slight shift in the rear axle. Replaced the lower control arms on both sides with Moogs.

 

Yeah....with my 2000 WJ, I felt a little rear end sway at speed so I checked the bushings and found the outer cans of the bushings were rotted. Being OCD about my jeep, I wasn't content with just replacing the bushings, but instead replaced all 7 control arms complete with bushings! It drove like it was on railroad tracks, tracking straight with no darting left or right and solid in turns, even high speed cornering! I replaced the front track bar as well. Everything was Moog from rockauto.com

It's a real pain to remove the old bushing without crushing the arms anyway. BTW, the front upper control arms only have one bushing in them. The other is pressed into the axle bracket and the arm is dropped over it with a thru bolt. MAKE SURE those bolts are tight on all mounts. They have to compress against the sleeves or they will wear out the holes.