I had the 99 SHO inspected and it failed because the inspector said both rear springs were broken. Not much of a mechanic so I got a local mechanic to replace the rear springs. I just bought the rear springs from Rock Auto that said they fit the car. Now, the rear end feels like it has air shocks that are fully extended going over any bumps or expansion joints. The rear end is super stiff. What are my options? Did the mechanic not properly replace the springs? Maybe he has the rear shocks in a bind? Not even sure if that's possible. Could both rear shocks be bad and need to be replaced? I don't want to just throw money at it. I want to know what might be the problem and get it fixed. If it needs new rear shocks then I'm fine with that as long as that's the problem. What do you think?