Ok I am posting this in the suspension board as well as the wheel and tire section because it could be one or the other. Im not sure. OK I have a 95z28 and over the weekend I put on new rims with new tires, 18 front 20 rear, and a new adj panhard rod. When I dorve the car to work today it felt like it was shifting around like I was driving on a wet road. Could this be because of the new panhard rod? New tires? Or something else? Also I did not have an alignment after getting the new tires. Do they need to break in first? The rear tires have 295/25/20s on them, the front has 285/35/18. Any help is greatly appreciated.

 

Is the phb adjusted properly? Are all the bolts tight?
It could also be the tires tracking.

 

Check the air pressure in the tires and make sure the rear end is centered on the frame with your new panhard.
Doug

 

So it's 3 days later, any luck with the previous suggestions???

 

Well, if you just went from the stock 16's, I bet it's just the tires tracking all over the road! LOL I just went from 16's all around to C5 rims 18" rear 17" front and I was like WTF! But all the cars with the bigger, wider tires catch every groove in the road and it pull all over. Just my .02 BUT I would DEFINATELY check to make sure that everything is tightened up & on correctly.
Mike