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1. Raise the rear of the vehicle and place on jack stands at the jack points. Remove BOTH rear wheels.

2. Underneath the car, use a 18mm wrench/socket to remove the lower shock bolt (Photo A - Red Circle). The shock is all that keeps the lower control arm from dropping, so it is a good idea to place another floor jack under the arm to catch it. I used a piece of 2x4 wood between the arm and the jack for protection.

3. Open the trunk. Pull back both sides of the trunk interior liner. The right side will require removal of the gas filler release cord cap (Photo B). Both sides have small plugs that can be removed by using a screwdriver to pop the center out, then removing the plug. I also found it a good time to pop the big black plug out of the center of the rear trunk wall liner.

3. The shock towers are behind black rubber mat covers. Remove this cover from the tower by pulling it towards you. It is split in the rear and should slide out pretty easily.

4. While having your assistant hold the shock, remove the two 13mm nuts from the shock mount bolts (Photo C). Remove the shock assembly from the wheel well.

5. Remove the 21mm nut from the shock bolt to remove the rear shock mount. Then, reattach the rear shock mount to the new Bilstein shock. If you have new rear shock mounts like I did, use them instead following their directions carefully.

7. Place the shock aside for now and attach spring compressors to the spring (Photo D). If you are lucky, you might be able to get away with having your assistant press down on the control arm and you can wiggle the spring out without the compressors, but it is tricky.

8. Once the spring is out, save the top rubber insulator. You will not reuse the lower insulator as this is where we will insert our rear adjustable spring perch (Photo E).

9. I found it easier to jack the control arm up a bit and hold the washer and nut underneath while dropping the perch down thru the hole in the arm. You can see the hole here (Photo A - Blue Arrow). It is a pain, but you will manage to squeeze the nut in there to get it started on the perch.

10. Tightening this nut is a bitch. There is no room for a socket because of the axle. What I finally ended up doing was to put a 1-1/16" wrench on the nut to keep it immobile and using a hex key wrench inserted into the end of the spring perch bolt to tighten it up. You might be able to get away with clamping something onto the spring perches threads, but I didn't want to damage them and Bilstein put the hex key in the end of the bolt for a reason. Make sure this nut is good and tight. Once finished, you can move your spring plate and lock nut up or down on the perch as desired before placing the new spring in. This adjustment controls your ride height. Moving the plate down will lower your car and vice versa.

11. Using the top insulator from the OEM spring, place it over the top of the new Bilstein rear spring. The rear springs are round, the cone-shaped springs go up front. Make sure the Bilstein lettering is upright. Have your assistant press the control arm down while you slide the new spring over the perch and up into place. It is much easier to put the new spring in since it is smaller. You can even compress the new spring by hand if needed. Your spring install is done, let's get the new shock installed.

12. Have your assistant place the new shock assembly back up into the shock tower while you fasten the shock into the tower inside the trunk (Photo F). Tighten to 21 ft-lbs.

13. If you have the PSS9 kit, twist the shock so the adjustment knob is to the rear of the car. Reattach the lower shock bolt. This may require using the jack to push the control arm up to line up with the shock bushing. Tighten to 74 ft-lbs. Shock is done.

14. This is a finished side (Photo G). Repeat these steps on the other side.

15. Replace all trunk liners and wheels. Jack the car up and remove the stands. Lower the car and admire your new drop in the rear.


Photo A

Photo B

Photo C

Photo D

Photo E

Photo F

Photo G

  © MarvelPhx