Strut inserts and rear shocks....DIY job?

Post in this forum for topics relating to suspension, steering, and brakes

Moderators: GRNSHRK, ron, bfons

Post Reply
ronnieg
Posts: 106
Joined: Sat Jan 12, 2013 4:07 am
Location: Denton, TX

Strut inserts and rear shocks....DIY job?

Post by ronnieg »

A few questions:

I'm pretty handy....I've rebuilt my front suspension, except for the strut inserts and mounts. Is new strut inserts and mounts a DIY job? Will have to take in the shop of alignment, so could just have them do it... would I be wishing I had them do it?

also, replace rear shocks while I'm at it? and are rear mounts more durable than front, or should I replace all shocks and mounts while at it?

shocks are originals. 80k miles.

lastly, will I notice much ride difference? I suspect so...but would like opinions...

Thanks
Happier in a 635
brickwhite
Posts: 797
Joined: Wed Sep 01, 2010 3:29 pm
Location: Broomfield, CO

Re: Strut inserts and rear shocks....DIY job?

Post by brickwhite »

If it is a TX Car, Rust should not be an issue.

Struts are pretty easy, just do a search of Google e24 or e28 strut replacement

McPherson Spring compressor would be needed.

I give it a 3 out of 5 wrench job.
- 12 535i
- 92 325ic
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Strut inserts and rear shocks....DIY job?

Post by Brucey »

unless they have fallen apart completely, the only way you can tell if you need new top mounts is by stripping the old ones out and looking at them.

What you will definitely need is new bump stops. You will need rears anyway (they don't come with new shocks) and if you don't have Bilstein front inserts you will need front bump stops too.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ronnieg
Posts: 106
Joined: Sat Jan 12, 2013 4:07 am
Location: Denton, TX

Re: Strut inserts and rear shocks....DIY job?

Post by ronnieg »

Brucey, it would be foolish to not replace 34-year old front mounts while it's all apart, right?

I just gave the rear shocks a bounce test, and they felt smoother and tighter than the fronts, so perhaps the rear mounts are in better shape. Will take a look. Have to remove the rear top mounts in any case to replace the shocks, correct?
Happier in a 635
User avatar
jps635
Platinum Member
Platinum Member
Posts: 872
Joined: Sat Feb 27, 2010 10:50 pm
Location: NZ

Re: Strut inserts and rear shocks....DIY job?

Post by jps635 »

Its relatively straight forward.
Couple tips:
- can be difficult to get the top central nut undone without an air gun - ok if you're binning your old inserts can grip the shaft.
- don't need to remove the rear seats to access the rear mounts, but may have to lie in boot in which case make sure the lid can't close and lock you in. A swivel head ratchet spanner makes this job much easier.
'85 635csi JPS (RA2-66)
User avatar
Hefeweizen
Posts: 2324
Joined: Thu Jul 17, 2008 1:24 pm
Location: Colorado Springs
Contact:

Re: Strut inserts and rear shocks....DIY job?

Post by Hefeweizen »

Either one, front or back is not that hard to do as long as you have a spring compressor and are able to open the top nut. I found it easier if you loosen them while the shock and the struts are still in place. I found it easier to remove the back seats to get to the third nut.
Rainer
03 330Xi (DD)
85 635CSi (RIP 3 May 19)
80 633CSi (Red Euro, Project)

"If you think a good European mechanic is expensive, try a bad one!"
ronnieg
Posts: 106
Joined: Sat Jan 12, 2013 4:07 am
Location: Denton, TX

Re: Strut inserts and rear shocks....DIY job?

Post by ronnieg »

Thanks to all. will report back in a few weeks.
Happier in a 635
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Strut inserts and rear shocks....DIY job?

Post by Brucey »

ronnieg wrote:Brucey, it would be foolish to not replace 34-year old front mounts while it's all apart, right?
there is just a bearing and a lump of rubber in there. There are only three forms of failure (corrosion aside);

1) bearing claps out
2) rubber collapses
3) rubber debonds from steelwork.

Unlike the rears you don't need to take anything apart at the front to diagnose any of these failures;

1) evident as roughness when turning the steering (have an assistant turn the steering whilst you have one finger on top of the strut centre), and/or vertical free play (apparent with the car on axle stands whilst you jack/heave the wheel up and down).
2) with the car sat on its wheels, there must be a gap between the 'top hat' and the underside of the top mount bolt flange. You should be able to get the short end of a 6mm allen key in this gap all the way round. If the rubber has sagged more than this the top mount is liable to clunk over big bumps.
3)when you jack the car up the front strut will pull out of the top mount.

IME front top mounts can look great and be awful or look horrible and actually work quite well. Rears are different, because everything is hidden. I do worry about replacement parts, because there is an important rubber to metal bond in the front top mounts; this would be the first thing to fail in a badly manufactured new part.
I just gave the rear shocks a bounce test, and they felt smoother and tighter than the fronts, so perhaps the rear mounts are in better shape. Will take a look. Have to remove the rear top mounts in any case to replace the shocks, correct?
It is unlikely that you have fully tested the rear top mounts by bouncing the car up and down. Because the rubber parts are hidden from view, you really need to take a look at them. If they are very bad the rear top mounts will rattle over stutter bumps, which is a good diagnosis in the absence of inspection. Yes the whole strut (including the top mount) ought to come out with the rear shock.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ronnieg
Posts: 106
Joined: Sat Jan 12, 2013 4:07 am
Location: Denton, TX

Re: Strut inserts and rear shocks....DIY job?

Post by ronnieg »

Brucey, thanks for all the tips.

With the front of the car on jack stands, using a lever I was able to feel some looseness in both front struts. Wheel bearings are tight, so not them. all the control arms and tie rod ends are relatively new. It feels as though there is either about 1/8 inch of un-damped "play" in the shock itself, or the top mount/bearing has some motion. Not sure if a shock can have a small "dead spot?"

Giving the car a bounce test, all four shocks seemed to dampen properly. But when I pull the car into the garage up a small ledge, I definitely feel something loose.

I'll check the space between the strut mounts and housing as you suggested.....

Thanks again
Happier in a 635
Post Reply