How to Replace Shocks, Struts, and Springs

Last Updated - August 3rd, 2004


Difficulty:    

Time Investment:  Under a Day

Go to Pictures:

Go to Instructions:
Front Suspension
Rear Suspension

Go to Tools Required:


Pictures:

Click on a picture to enlarge it.

New Eibach lowering springs
Comparison of front Eibach spring to stock spring with 115k miles. Comparison of rear Eibach spring to stock spring with 115k miles. Old struts and shocks.  Note that the struts and shocks aren't extended...  You can pull them out and they will happily stay in that position too.
Shown here are the top front spring seat, bearing plate, lower spring spacer/sleve, and boot.
The boot assembly is made up of a rubber stopper, a hard ring that the boot wraps around, and a cable tie to hold the bottom of the boot to the strut.
Here's a happy Koni strut adjusted.
The boot is placed over the strut.
The spacer/sleeve is added.  (Note, that this part is listed in the FSM but wasn't on Mike's IROC or Daytonastein.
Here's the rubber stopper and the ring that holds the boot.
The rubber stopper is inserted over the end of the strut.  (Tight fit)
A spring compressor is used to squeeze the spring down.

Here's another shot of the compressed spring.
The top spring seat is placed over the spring and the bearing cap is secured using a large nut.
After releasing the spring from the compressor, the ends of the spring compressor had to be wiggled out with the help of a small pry bar.
Here's a shot of the strut tower.  Note the three nuts that hold the bearing cap to the underside of the tower.
Rear Driver's Side Shock Rear Passenger Side Shock & Spring
After the top is secured, the bottom is fitted onto the steering knuckle.
Here's the mounted strut.
Drivers side rear shock with axle jacked up. Passenger side rear shock & spring.


Instructions:

Note:  After changing your suspension, you should get your car aligned so that it rides correctly.


Front Suspension

The front strut assemblies include the strut itself, a compressed spring around the strut, and a bearing cap to hold the spring onto the strut.  The whole thing is installed and removed as one piece.

1.  Position the car where you have good access to the front wheel area.

2.  Jack up the front end of the car, put it on jack stands, and remove the front wheels.

3.  Remove the 2 through bolts that hold the bottom of the strut to the steering knuckle.
These will likely be very tight.  It may take everything you have to muscle the nuts off.  A beefy impact wrench would be great here.

4.  Remove the 3 nuts that hold the strut bearing plate to the underside of the strut tower.

5.  Wiggle the old strut/spring/bearing plate out.
When you do this, the top of the steering knuckle will all outward.  As a result, the halfshaft may pull out of the transaxle and start leaking oil.  Make sure to have a pan ready to catch the oil.

6.  Compress the spring with the spring compressor.
You should get the hooks around as many coils as you can.  If you hook too few, you'll compress the spring as far as it will go and then have to uncompress it to grab an additional coil.  An air rachet or impact wrench is awesome here.  Doing this by hand will take a VERY long time.

7.  Remove the nut holding the bearing plate to the strut shaft.
This will be tight as well.  An offset box end wrench around the nut with a socket in the middle works best.  You can also used an open end wrench but you can't get a hold of the whole nut.  With both wrenches in position, it's often easiest to lay everything down so one of them is against the ground and the other is in the air.  You can then push on the one in the air or whack it with a hammer (for hammering, a breaker bar would be better than your precious rachet).  You may end up stripping the hex head on the strut shaft.  If so, you can get more agressive and take some vise grips to that part.

8.  Disassemble all of the parts, noting the position and orientation in which they were installed.

9.  Inspect all of the parts and reconsider what you want to replace. 
The upper spring seat may be heavily rusted and broken.  It has a rubber outside with a metal inside.  The bearing plate is similar and may simply be beat to hell after say 100,000 miles.

10.  If you have adjustable struts, adjust them per the manufacturer's instructions.

11.  Put the lower spring seat/sleeve on the strut.
This piece didn't exist on Mike's IROC or on Daytonastein.  Where did it go???  Good question.  It was in the FSM so Mike ordered one from some internet parts store for the IROC.  The Daytonstein continues without one. 

12.  Assemble the pieces of the strut boot.
This will probably vary based on what you get.  On the model pictured above, there is a hard plastic ring that fits over a rubbery stopper.  The top of the boot catches on the ring and the bottom of the boot is secured to the strut with a cable tie.  Not too high tech.

13.  Put the spring on the strut.

14.  Compress the spring with the spring compressor.
Make sure you get enough coils in the compressor to adequately compress the spring.  Four should be your goal.  If you don't get enough in there, you won't be able to get the bearing plate on and you'll have to release the springs and try again.  If at all possible, use an air rachet or an impact wrench.  This will take a REALLY long time otherwise.  Also, you will likely scratch up the sides of the base of the strut that supports the spring.  Just do your best.

15.  Put the upper spring seat on the strut.

16.  Install the bearing plate on the top of the strut.
Use the same technique you used to get the old strut assembly apart.  Keep in mind that you can strip the threaded part of the strut shaft if you aren't careful.

17.  Uncompress the spring.

18.  Looking at the orientation of the studs in the bearing cap and the lower bolt flanges, twist the bearing cap so that it will be roughly aligned with installed.

19.  Attach the strut assembly to the strut tower.
You can wedge it in there so that it's sitting on some of the parts around the knuckle with the bearing plate up in the strut tower.  Then stand up, stretch your back, and lift the assembly up while looking down through the top.  It should be relatively easy to get the studs to line up with the holes.  When they do, hold the assembly up with one hand and quickly install one of the nuts with the other.  This will be easier than you will expect.


20.  Rotate the bottom of the strut as appropriate and attach it to the steering knuckle.
Try to get the knuckle/strut joint locked down at an angle so that the brake rotor is as close to vertical as possible.  You'll still need an alignment, but there's no reason to make it worse than it has to be.

21.  Repeat this process on the other side of the car.

22.  Have your car aligned by a local shop as soon as possible.



Rear Suspension

Prior to starting, first consider how the rear suspension works.  The springs are compressed slighly and push outward between the body and the rear axle.  The shocks are in tension pulling the axle and body together against the springs.

1.  Position the car where you have good access to the rear wheel area and behind the rear bumper.

2.  Jack up the back end of the car, put it on jack stands, and remove the rear wheels.

3. Jack up the rear axle.
This can be done with a single floor jack placed in the middle of the rear axle or with two separate jacks.  Since the car is already on jack stands, you'll probably need a couple wood blocks to get your jack tall enough.  In the pictures above, a single jack was used on the end of the axle, this worked, but Mike had to prop up one side and then move the jack to the other side during reinstallation.  In that case, he did one side at a time.
 

4.  Remove the rear shocks.
There is a single bolt on the top and bottom of each shock absorber.  On the bottom, the nut is welded in place so all you need to do is unscrew the bolt.  On the top, the nut is free so you'll need two wrenches.  Space is tight on the nut side.  One way to hold the nut is to place a 3/8" drive socket over it and then partially insert a 3/8" ratchet into the socket.  Then with the bolt side, use an air ratchet or your 1/2" ratchet. Once the shocks are removed, the springs are going to be pushing the axle down and nothing is going to be holding up up but the jack you have supporting it.  

5.  If you aren't installing new springs, put the new shocks on now, ignore all further steps, and reassemble in the reverse order.

6.  Lower the jack to extend the springs.
The FSM advises you to be careful not to stretch your brake lines while doing this.  Just let the jack down slowly until you can pull the springs out.

6.  If the rubber spring seats are torn up, replace them now.
These are something you will most likely not find at your local parts store so plan on ordering them in advance.  You can see them pretty well without removing the shocks or springs so you can plan ahead.

7.  Replace the springs.

8.  If you have adjustable shocks, adjust them per the manufacturer's instructions.

9.  Attach the tops of the new shocks.

10.  Jack the rear axle back up to realign the holes in the mounts with the lower holes on the shocks.
This may take a little adjusting of each side as you jack up the back.

11.  Replace the lower bolts.

12.  Remove the jack, put the tires back on, and lower the car.


Tools Required:


Front Suspension

Rear Suspension