ok the cars an 86 z28 with stock rims and suspension parts. last winter i went outside one day and the pass. rear was down about 3-4" lower then usual and the driver rear was up about 2" higher. i replaced the pass. shock and it did nothing. I don't know anything about suspension but everything under the car looks ok. everything is bolted in and nothing looks broken. The only thing that i thought of was possibly a bad pass spring, but before i go and spend the money i was hoping for some advice.

 

I'm guessing spring as well, but it would help if you got some pictures of the car. Get a few from under the car and of how the car sits.