Stange Vibrations

I have a 96 Cherokee and it has 31's with NO lift....It dosnt rub much but when I hit a hill hard or climb something fast it rubs slightly....The steering wheel starts vibrating around 55mph but is fine anywhere under that....I took the Jeep out the night beofore but didnt do anything crazy and it was fine all last night and this morning...After i washed it later the next day it started doing this any ideas?????....

You got mud in your rims??

Are the weights that balance your tires still there?

How old are your tires? I had strange vibrations especially when hit a bump on tires that looked OK, then I changed them and the vibrations disappeared.

yeah there might be mud in the tires and the weights may have came out also...I think im gonna get the tires aligned and take a look tomorrow....

It ended up being mud that was still packed under the rim...even after I washed it...Thabks alot guys maybe this will help spmeone else..