Porsche 996 Turbo Bilstein PSS10 Suspension Install

I finally decided to upgrade the suspension on my Porsche 996 Turbo.  The car previously had street H&R coilovers but was just not happy with the performance so I decided to switch to the Bilstein PSS10 and at the same time install Eibach sway bars and GT3 control arms for additional camber in the front.  Eibach rear sway bar ended up not fitting so I exchanged it for the H&R, Eibach was rubbing on the subframe.  I will start with the front suspension since it is a little more involved than the rear.  I will also replace the front axle boots since they are starting to show signs of cracking.

Front Suspension:

1. Start out by removing the 32mm axle shaft nut.  If you don't have an impact wrench, remove the wheel center cap and unbolt it using a breaker bar with the wheels on the ground.  If you have an impact wrench you can remove the wheels and unbolt the nut.

 2.  Now it is time to remove the caliper and the brake rotor.  Before unbolting the caliper disconnect the brake lining sensor and the ABS sensor.  Unbolt the bracket that holds the wear sensor, the ABS connectors and the brake line to the wheel carrier.  Use a wire or a hook to hang up the caliper so the rubber line doesn't get damaged.  Remove the rotor set screws and remove the rotor.

3.  Once the rotor is removed, remove the rotor backing shield.  You are basically removing it so you have room for your ball joint puller tool.

4.  Use a ball joint puller, such as Hazet 1779-1 to disconnect the tie rod.

5.  Use an air hammer to drive the axle shaft out of the steering knuckle.

6.  I don't own a ball joint puller tool that is of a proper size to remove the control arm ball joint out of the steering knuckle so what I did instead is unbolted the control arm and the control arm link from the subframe and I will remove the steering knuckle with the control arm attached.  When working on the driver's side, don't forget to disconnect the headlight level sensor from the control arm.

7.  Disconnect the sway bar end link from the strut assembly.

8.  Open the hood and unbolt the strut mount from the chassis.  Hold the strut assembly with one hand so it doesn't fall down.  Remove the strut assemble out of the car with the steering knuckle and the control arm attached.

9.  Here is how it looks removed out of the car.  I am now going to remove the axle shaft and replace the boots.

10.  I am going to remove the diagonal braces for easier access to the axle shaft cv bolts.  Those also need to be removed to get the sway bar out later on.

11.  To replace the axle shaft boots remove the axle shafts, knock the cover off the inner CV joint.  Remove the circlip,  mount the axle shaft in a vice and by using a piece of wood knock off the inner CV joint off the shaft.

12.  With the CV joint removed, slide off the old boots and install new boots.

13.  Once you disassemble the old struts be sure to clean, inspect and re-lube the strut upper bearing. 

14.  Here is the PSS10 strut fully assembled and ready for the installation.  When installing the strut mounts, be sure the arrow on the mount points towards the front of the car.

15.  Let's install the sway bar.  Nothing special here, support the subframe with a jack or a jack stand.  Unbolt the subframe bracket and remove the sway bar.  After installing the new sway bar torque the sway bar M10 bolts to 46Nm or 34ftlb.  Tighten the side bracket to 100Nm or 74ftlb.

16.  If you removed the axle shaft to replace the boots now is a good time to reinstall it.  Torque the M8 bolts to 39Nm or 29ftlb.

17.  Mount the assembled PSS10 strut into the steering knuckle and torque the M12 bolt to 100Nm or 74ftlb.  Be sure to use a new lock nut.  I would bolt up the control arm at this point as well since there is no room for the torque wrench when the axle shaft is installed.  Torque the control arm to steering knuckle nut to 75Nm or 56ftlb.

18.  Now we can bolt up the tie rods, torque the nuts to 75Nn or 56ftlb.

19.  Install the brake rotor dust shield, the brake rotor and the caliper.  Use some blue Loctite on the brake shield bolts.  Torque the caliper bolts to 85Nm or 63ftlb, always use new bolts.

20.  You can bolt up the diagonal arm to the subframe and torque the bolt to 160Nm or 118ftlb.

21.  Install the sway bar end link and torque the bolts to 46Nm or 34ftlb.

22.  Torque the diagonal arm to subframe to 160Nm or 118ftlb.  Do not tighten the diagonal arm to control arm bolt until the car is on the ground with the suspension at rest.  Leave the control arm to subframe bolt loose also.

23.  Install the wheels and with the center cap removed torque the axle shaft nut to 460Nm or 340ftlbs.  

Rear Suspension:

1.  Remove the trim around the subwoofer opening.  You will see a bolt at the bottom,  remove the bolts on each side.  Flip the subwoofer and disconnect the wiring harness.

2.  Remove the square piceses of carpet that cover the shock mounts.  Pull up the rest of the carpet so you have access to the subwoofer bracket.  Remove the subwoofer bracket.

3.  Unbolt the shock mount bolts.

4.  Disconnect the sway bar links from the shock absorber.  

5.  Since I am replacing the sway bar, I am going to unbolt it from the subframe and remove it.

6.  Mark the shock mount position.

7.  Unbolt the shock from the wheel carrier.

8.  Remove the adjustment knob from the PSS10 shock and install the shock mount.

9.  Here is the fully assembled shock ready to be installed.

10.  Install the new PSS10 shock into the car and bolt up the top shock mount nuts.  Torque the nuts to 46Nm or 34ftlbs.

 

11.  Bolt up the lower shock absorber mount to the wheel carrier but leave the bolt loose until the car is on the ground.  It is kind of tricky installing the lower bolt because the shock needs to be slightly compressed.  What I did is I put the jack stand under the lower shock mount and lowered the car a bit.  I then used a screw driver to align the shock mount hole with the wheel carrrier hole and inserted the bolt.

 

12.  Now I'll install the rear sway bar.  Torque the sway bar subframe mounting bolts to 23Nm or 17ftlbs and torque the sway bar links to 50Nm or 37fltlbs.

Finishing up:

Before you go for a test drive don't forget to torque down the bolts you left loose.  Ideally you want to do this on a lift but most of us don't have one.  What I do is a jack up the car and lower it down on the ramps, this isn't ideal but better than nothing.  I usually ask the alignment tech to loosen the bolts that can cause bushing preload and retorque them.  The bolts that you need to tighten are the diagonal arm to control arm to 160Nm or 118ftlbs, control arm to subframe needs to be torqued to 120Nm or 89ftlbs.  In the rear all you have to torque down is the shock absorber lower bolt to 110Nm or 81ftlbs.  Torque the lug bolts to 130Nm or 96ftlbs.