BMW E85 Rear Shock Replacement – 2002-2008 Z4 – All Models

0
4997
BMW Z4 rear shock replacement

BMW E85 Rear Shock Replacement – 3 Hours

repair models
BMWZ42.5iM54 2.5L
BMWZ43.0iM54 3.0L
BMWZ43.0iN52 3.0L
BMWZ43.0SiN52 3.0L
BMWZ4M RoadsterS54 3.2L
difficulty bar
The Repair Difficulty Level displays graphically how challenging the repair is, from easy to advanced. Easy repairs usually require very few tools, have short repair times and do not require jacking and supporting the vehicle. As the difficulty level rises, expect the repair to demand more time, specialized tools, and better understanding of mechanics to complete the job.

The BMW Repair Guide used this 2005 Z4 for the following article. To see other repairs on our site using this actual car, please click on the image below!

4usbt33585ls58274

Repair Summary
The following article gives detailed instructions on performing a rear shock absorber replacement on a BMW E85 Z4 series car. Even though we have used a 2007 BMW Z4 2.5i to perform this installation, this article can be applied to any E85 Z4 series vehicle produced from 2002-2008.

You will first recognize the need for a BMW E85 rear shock replacement in your backside. Worn out rear shocks and shock mounts cause a rough and noisy ride – expect to change out your BMW Z4 rear shocks every 100,000 miles.

The BMW Z4 is a great car, plain and simple. It is one of our personal favorites here at the BMW Repair Guide. Its design is iconic…it’s handling is superb. The BMW Z4 is just a fun car to drive, especially here in South Florida where we can enjoy the retractable top for most of the year. The BMW Z4 is known as a pretty solid car, and when maintained properly and driven with respect (watch the pot holes and speed bumps) your suspension should give you hundreds of thousands of trouble free miles.

A BMW E85 rear shock replacement should be considered a normal maintenance item and we suggest it’s performed before your teeth start rattling – about every 100K miles. The Z4’s low stance and artful handling tends to place greater loads on the rear shocks, which in turn tends to wear down the trunk located rubber shock mounts. A tell tale sign of a worn rear shock mount is a “clunking” sound coming from the trunk on rough roads or tight turns. In extreme cases of neglect, the shock mounts have been know to cause structural damage to the body of the vehicle as they try and pull out of their mounting holes. Newer shock mount kits include an aftermarket reinforcement plate to eliminate this catastrophic problem – we highly suggest using this plate on any BMW Z4 rear shock replacement.

BMW E85 rear shock replacement is a rather simple, straightforward repair for the DIY mechanic…EXCEPT FOR ONE CAVEAT; the adjustable soft top stowage base in the rear of the Z4 trunk must be removed to gain access to the top of the rear shock towers. We will be up front with you now…this is a very tricky part of the repair and requires extreme patience and the heartbeat of a yoga master to reassemble. We detail every step from removal to reassembly to make the repair journey as comfortable as possible for you. Again…it can be done! And doing it yourself will save you hundreds of dollars from taking it to a local independent mechanic that has probably never done the repair themselves either.

Affiliate link disclosure – The BMW Repair Guide uses affiliate links in their site. For more information on affiliate links, please click here.

1. Rear shock absorbers (required) We have listed several quality options depending on your budget and model car.

Shock Absorber Rear – Bilstein 19-158983

All E85 Z4 except M sports suspension

Shock Absorber Rear – Genuine BMW 33526785996

All E85 Z4 except M sports suspension

Shock Absorber Rear – Bilstein 24-141680

All E85 Z4 M sports suspension only

Shock Absorber Rear – Genuine BMW 33526785997

All E85 Z4 M sports suspension only

2. Rear shock mounts (required) – Always replace your shock mounts with your rear shock absorbers.

PartQuantityPart #Description
Shock mount – 79670233526779670OEM Febi – All E85 Z4 models

 

3. Rear shock mount reinforcement plate (optional) – After years of being under stress from the shock absorbers, the sheet metal in the Z4 wheel wells has been known to fail. Prevent catastrophic damage to your rear suspension by adding a pair of reinforcement plates when replacing your shocks.

PartQuantityPart #Description
Shock mount reinforcement plate – S02KT1002478ECS02KTECS Tuning – All E85 Z4 convertible models (except M coupe)
Shock mount reinforcement plate – S01KT1002478ECS01KTECS Tuning – E86 Z4 M coupe only

 

4. Shock bump stops (optional) We list bump stops as optional, but very rarely will you be left with anything that can be reused. The bump stops deteriorate over time and fall apart. We suggest replacing them every time you change out your rear shocks.

PartQuantityPart #Description
Bump stop – 78546233536778546Genuine BMW – All E85 Z4 models except M.
Bump stop – 70350233536770350Genuine BMW – All E85 Z4 M models only


Floor jack – low profile
Jack stands
17mm socket wrench with Breaker Bar (for wheel lug nut removal)
Torque Wrench
10mm socket wrench
13mm socket wrench
16mm socket wrench
18mm socket wrench
17mm open end wrench
Adjustable wrench
Screwdriver – flat blade
Pliers – needle nose

Section 1  – Removing the adjustable soft top stowage base.
In order to gain access to the BMW Z4 rear shock mounts, the trunk’s folding top compartment must unfortunately be removed. BMW really should have put more thought into this during the design of the Z4….for removing and ESPECIALLY reinstalling the compartment floor is a royal pain in “das arsche“. Take it one step at a time and move slowly.

  1. The first step is to turn the side mounts and raise the compartment floor to its top position. Release the cover from the compartment floor by pulling it loose with your hands…it is clipped on and just snaps on and off.BMW E85 rear shock replacement - raise the convertible top compartment floorBMW E85 rear shock replacement - release the compartment cover
  2. With the compartment floor in the raised position, it is time to remove the infamous plastic clips that anchor the floor to the side mounts. There are four plastic clips, two on each side of the compartment floor, that must be removed. The following image shows the plastic clips on the left side of the floor. In order to remove them, you must squeeze the lobes together then push them UP and out. Be careful when pushing them up and out…they can get lost behind the top and you will be stuck ordering new clips (use the following link to order new clips if you break or lose any – Soft Top Cover Clip – 13270).BMW E85 rear shock replacement - unclip the shelfSqueeze the clips then push them up through the shelf
  3. With the four clips removed, it is time to remove the compartment floor from the trunk. The compartment floor rests on the side mounts hinged rails. To remove, gently lift up the floor until it releases from the rails on each side mount. ***Important Note – the compartment floor has a tab on the rear of it that activates the convertible top’s microswitch (allows the top to be raised or lowered). Use extreme care when removing the compartment floor from the trunk so you do not break the microswitch (located on back wall of trunk). If you break the microswitch, you will not be able to raise or lower the top until replaced.BMW E85 rear shock replacement - push the floor up to release from the railsRemove the compartment floor
  4. Use a 10mm socket wrench with extension to remove the two bolts anchoring the side mounts to the trunk. BMW E85 rear shock replacement - remove the side mounts
  5. There is a plastic rivet on top of each side mount that needs to be removed as well. Use a flat blade screwdriver and a pair of needle nose pliers to remove the stem from the fastener. Then just pry the fastener out with the screwdriver. Remove the side mounts from the trunk when you have finished removing the rivet.BMW E85 rear shock replacement - remove the side mountsBMW E85 rear shock replacement - remove the side mounts

 

Section 2 – Removing and installing the rear shock absorbers.

  1. Jack and support the rear of the vehicle using the jack stand method. Please click here to learn how to properly jack and support your vehicle for this repair.
  2. Using a 17mm deep well socket, remove the lug nuts and rear wheels.
  3. Starting in the trunk, you will need to remove just enough trunk liner and rubber insulation to expose the top of each shock mount.BMW E85 rear shock replacement - locate the shock mounts in the trunk
  4. Start by removing the left side panel cover by twisting the release handle and pulling free of car.Remove the left panel cover
  5. Pull the trunk liner and the underlying rubber sound insulation away from the side of trunk exposing the shock mount. There is one plastic rivet that will have to be removed near the back of the trunk…use a body trim tool to remove it. ***It is common for the rubber sound insulation to break apart when removing – this is normal and does not affect the integrity of the vehicle in any way. If you are interested in replacing your rubber insulation you can order here or in the parts section above. Order new left trunk rubber sound insulation by clicking here. Order right trunk rubber sound insulation by clicking here.BMW E85 rear shock replacement - remove the plastic rivetBMW E85 rear shock replacement - pull the sound insulation back
  6. Position a floor jack under the left rear wheel hub. Jack up the hub about 6″ to release the pressure on the shock…this makes the shock easier to remove and install.BMW E85 rear shock replacement - use a floor jack to raise the wheel hub 6"
  7. Use a 13mm socket wrench to remove the two nuts anchoring the shock mount to the vehicle chassis. Note that on the BMW Z4 you cannot get a socket on the self locking plate nut because stowage base frame is in the way. It can only be removed after the shock is removed from the vehicle.BMW E85 rear shock replacement - Remove the shock mounting nuts
  8. Use an 18mm socket wrench to remove the lower shock mounting bolt. This bolt will be tightly torqued…use a breaker bar or a piece of galvanized pipe to help break the bolt free.BMW E85 rear shock replacement - remove the lower shock mounting bolt

    One of the best tools you can have in your shop is a 24″ piece of 1″ galvanized pipe, purchased at any home improvement store. Simply slip it over the handle of a 3/8″ or 1/2″ ratchet and you have just created a great breaker bar that will free any stubborn bolt!

  9. Remove the rear shock from the vehicle and place in a bench vise for disassembly. There are some parts on the old shock assembly that will be reused.Disassemble the old shock
  10. Use a 16mm socket wrench to remove the shock mount nut. Make sure the shaft of shock is tight in the vise…it will want to spin with the nut.BMW E85 rear shock replacement - remove the shock mount lock nut.
  11. Remove the top washer, the old rubber shock mount, the shock mount plate, any remaining bump stop, and the guard tube from the shock. Do not discard any parts you plan on reusing.BMW E85 rear shock replacement - Don't discard any parts you are reusingBMW E85 rear shock replacement - guard tubes.
  12. Now its time to set up the new shock for installation. Lay the new shock on a bench. Start by installing a guard tube (open end of tube faces bottom of shock). Next add the new rubber bump stop, the shock plate (concave side down), and the new shock mount.Install the new guard tubesBMW E85 rear shock replacement - install the bump stopsBMW E85 rear shock replacement - install the shock plateBMW E85 rear shock replacement - install the new shock mount
  13. Place the shock in a vice (or any other means) to hold it steady. If you use a vice, make sure to wrap rags around the shaft so you don’t score them. Using a 17mm open end wrench and an adjustable wrench, install the self locking nut on the top of the shaft (see image below).
    Tighten the shock lock nut
  14. Insert a new gasket on shock mount (gasket should have been included in shock mount kit).BMW E85 rear shock replacement - install a new shock mount gasket
  15. Insert shock back inside wheel well. Install lower mounting bolt and torque to 100 Nm (74 ft-lb).Install the new shock back in the vehicle.Torque the lower mounting bolt
  16. If you are installing a new shock mount reinforcement plate (which the BMW Repair Guide highly recommends you do) position it on top of the shock mounts as shown below.BMW E85 rear shock replacement - install new shock reinforcement platesBMW E85 rear shock replacement - shock reinforcement plates
  17. Install the two 13mm nuts and torque to 28 Nm (21 ft-lb).BMW E85 rear shock replacement - torque the shock mount nuts
  18. Replace the rubber insulation and trunk liner. Repeat installation on right side of vehicle.

 

Section 3 – Installation of adjustable stowage base.

    1. Reinstalling the stowage base side mounts is easy…just replace the two 10mm mounting bolts and plastic rivet as shown in the above steps.
    2. Reinstalling the stowage base compartment floor is ridiculously difficult and will definitely test your patience. But look at it this way…even the most seasoned mechanics struggle with it, and it does not take any more skill or knowledge than you already have. It is just really tough to get the floor mounted correctly on the hinged rail while reinstalling the plastic clips. The two rear clips are are extremely nauseating to install since you have to wedge your entire arm above the stowage base to insert them. If you get upset, walk away and cool off. You can even send us a nasty email to vent your frustration…we will be more than happy to talk you through it. But it can be done, and you will do it. Our best advice is to get someone to help hold the compartment floor in place on the hinged rails while you try and install the plastic clips. Start with one side, and install the front clip first. The front clip is relatively easy and will help keep the floor in place while you grapple with the rear. The following image shows the proper alignment of the plastic clip for reinsertion into the floor:Proper plastic clip orientation when installing the compartment floor
    3. Once you get all four clips in, verify the tab on the back of the compartment floor is properly aligned in the convertible microswitch.

BMW E85 rear shock replacement - compartment floor installation

BMW E85 Rear Shock Replacement Finished
If you have any questions or comments, please feel free to contact us. And congratulations for Doing It Yourself!

The Repair Difficulty Level displays graphically how challenging the repair is, from easy to advanced. Easy repairs usually require very few tools, have short repair times and do not require jacking and supporting the vehicle. As the difficulty level rises, expect the repair to demand more time, specialized tools, and better understanding of mechanics to complete the job.
BMWZ42.5iM54 2.5L
BMWZ43.0iM54 3.0L
BMWZ43.0iN52 3.0L
BMWZ43.0SiN52 3.0L
BMWZ4M RoadsterS54 3.2L