The rear of the first generation CTS-V has nivomat shocks that have the ability to adjust the ride height to compensate for passengers and other luggage in the rear. When you put lowering springs on this car, the rear will sense that it is too low, and the shocks will slowly raise the vehicle back up to stock height as you drive. A bumpy ride will also result as the shock will ride stiffer. My kit relocates the shock over 2.5 so that you can lower your car by trimming the stock springs, or installing the popular H&R, or Eibach springs sucessfully. I have sold over 600 sets and have not had a return. You will get everything you need for this installation, parts, hardware, instructions etc. You just need shorter springs. The black car pictured is 100% stock just my kit, 1 full coil removed from stock springs, and 14 trimmed from stock bump stops. Look up mightymouse solutions on facebook for more customer photos!