Front shock replacement advice

[markwascher]

How difficult is it to replace the front shocks on the e28 M5? Do I need special tools? I have never done this before but am eager to try. Is it a bad idea to jack the car up with the jack on the subframe? What shocks are recommended Koni vs Bilstine?

The ride is currently harsh and undamped when hitting small holes and cracks in the road. The front end is in good shape with a new drag link installed. All other components are sound. I think the existing shocks are Koni and may be adjustable. The steering is a little vague unless I am actively steering and cornering. Could this be a symptom of bad shocks? When I do a "push down" test on the front I can barely get it to move, maybe an inch or two with approx 150lbs of force.

Thanks for the help!

[Mark_88_M5]

in it, it will also have the tools necessary to complete the job safely. The only major tool that the home mechanic may not have will be a coil spring compressor, which I consider necessary. Air tools make the job much easier but are not necessary. I would put front strut cartridge replacement at about a 4 or 5 on a scale of ten.

Your choice of shocks will depend on what you want to do with the car. Do you still have the SLS rear suspension? If so and you are not planning on tracking the car I'd recommend going with stock replacements and enjoy the "touring car" ride. If you are going to track the car you will need to balance the front and rear suspension components and settings.

If you do have adjustable Koni's on the front they may be rebuildable, you will have to research that if you can have the car down for the turn around time.

I jack my E28's with a hydraulic floor jack (with a piece of 2 X 6 pine on the jack pad) under the factory jacking points. I will then put jack stands under the subframe rails in the front and/or under the rear subframe when working under the car.

[markwascher]

The factory SLS was replaced with a Dinan stage 1, seven years and 56k miles ago. The front struts and shocks are indeed Koni and are both externally adjustable. It seems to me that unless the car has been driven hard over rough roads that the struts and shocks should last more than 60000 miles. No? I am wondering if they simply need to be adjusted. I will call the guys at Dinan and get their input.

Thanks for your help! I will post the response from Dinan once I get it.

[Bruce in Canada]

was not a hard job, I borrowwed a spring compressor .
I put in Factory original shocks.. same part number as a 635.

I am happy with them so far.
only driven a few miles on them though.

I spent most of my time time cleaning everything in the wheel wells to make it look all new in there.

[warp1]

Maybe all you need is an adjustment on those shocks. Your 'test' simply revealed the higher rate springs they probably used. The test for the shocks is to determine if they're still *damping suspension motion*. And if you can't induce the motion, it ain't much of a test. ;^)--
C.R. Krieger
'88 535is - Da Red Dog

<img src="http://memimage.cardomain.net/member_images/2/web/578000-578999/578895_4_full.jpg">

[Matt Hernandez in Woodbridge, CA]

3 Steering knuckle bolts: 17mm socket/extension/breaker bar
2 caliper bolts: 19mm/breaker bar
1 Sway bar endlink nut at strut: 2 17mm wrenches (combination)
3 Strut mount nuts: 13mm/ratchet
1 strut nut: 19mm/breaker bar ( you may need to hold the piston in place with a pipe wrench and put a paper towel over it so you dont take a knick out of the piston)
1 female allen bolt: not sure of size but its fairly small

1 floor jack or stock jack will work
2 jackstands
13mm socket
17mm socket
19mm socket
Small allen key, not too small
extension about 6 inches
Big flattip screwdriver to pry off caliper
breaker bar
ratchet (helps)
pipe/monkey wrench
skin on knuckles

lift the whole front end when you do the job, its a PITA to get the sway bar aligned cause its under load when one wheel is on the ground.

Use a torque wrench if you cant torque in your head.

NOTE: i have done this job LITERALLY over 30 times lol
i can do both struts in an hour now O_O


Harsh rides are all suggestable, i have coilovers and its quite tolerable, then again, everyone says its cause im 22 haha. its just firm if anything and i like sporty rides. With Koni's you generally can adjust the rebound or expansion valving of the shock/strut cartridge.

www.koni.com for more info


I have revalved bilsteins and 520/380 pound springs, and as long as you arent speeding the car feels like a "new" car. The same bump at 100+ MPH vs 65 MPH is a noticable difference.

[markwascher]

So the shocks are adjusted, not needing replacement, phew! But the front end hunts and grabs crack like a junkie. It acts like it needs a castor adjustment. According to my alignment shop the castor of the Dinan Stage 1 is within spec. 8.5 left and 8.4 degrees right. Dinan specs are for 8.0 with +- .5 degrees.

Has anyone had this issue?

[Mark 88 M5]

running. These front ends get "twitchy" with any tires much larger than a 225/50 X 16" especially "High Performance" read stickey rubber.

[Mark 88 M5]

[Matt Hernandez in Woodbridge, CA]

That happens when you start stiffening up the suspension, shocks for example even stiffen up the car depending on dampening rate.Check your toe angle, they should be toe-in , the front end also likes to have random left or right alignment issues when there is almost no toe in or toe out, ask me how i know O_O

[warp1]

The only alignment adjustment for the E28 front end is toe-in/toe-out.

What usually causes 'tracking' like this is, as Mark has suggested, too-wide tires. If your suspension arm bushings or any front end ball joints (there's at least 9 of them) are loose, that can easily be a problem, too.--
C.R. Krieger
'88 535is - Da Red Dog

<img src="http://memimage.cardomain.net/member_images/2/web/578000-578999/578895_4_full.jpg">

[markwascher]

Running brand new (1300 miles on them) Continental "contiextremecontact" 225/50 R16 on factory wheels.

Glad you asked because there is severe inside tire wear after just 1300 miles! And there is a puddle of steering fluid the size of a salad plate on the floor. uuugghhghg. There was no leak before the suspension work described below.

The tires were mounted by Les Schwab in Warrenton. I had them check the alignment to the Dinan specifications provided. They told me the alignment was fine but I had a bad center link. My mechanic checked the center link (which was bad)and the rest of the suspension (which was tight) and replaced the center link with a Meyle. Replacing the link should not have affected the aligment, right? The old tires did not have inside wear. I have not hit anything, big holes, curbs or otherwise. Is it possible that my mechanic f'd up the alignment when installing the center link? The center link is not threaded or adjustable so as long as its the right one...

I am having the alignment checked again today. Somebody owes me some new tires and a sterring pump overhaul.

RATS

[markwascher]

The toe was out by -2.0 degrees on both wheels! Somehow the mechanic screwed up the alignment when he installed the center link. He is buying me new tires.

Thank you all for your input, sorry to waste your time.