DIY e30 suspension tips (long)

[Rob Clark <rclark@xxxxxxxxxx>]

Over the four day weekend, I installed new Bilstein Sport shocks,
Eibach HD springs, and rear shock mounts on my '87 325is.  Here are 
some tips for those considering a similar job.

The following info supplements the directions in the Bentley service
manual.  The step #'s correspond to steps in the Bentley.  Many of
these points might be obvious to the more experienced garage veterans,
but would have saved me a bunch of time if I knew them beforehand.



Tools:
- -------------------------------------------------

   Breaker bar
   Socket set, & wrenches (used 13, 17, 19 mm, and possibly others)
   Pickle fork set   (for tie rod & control arm joints in front.  I
       I bought a set of 3 from Sears, and used 2 of 'em)
   Torque wrench
   Spring compressor (buy/rent a good one!  I don't want to be
       around to see a spring compressor break!)
   Adjustable wrench with teeth

Parts:
- -------------------------------------------------

   Shocks & self locking nuts (the bilsteins came with the nuts)
   Self locking nuts for control arm and tie rod joints.  (I skipped
       these, because I will be taking apart the front again within
       the next month.)
   Springs
   Also, might be a good time to replace front & rear shock mounts,
       and control arm bushing in the front.  You might need a
       special tool to replace the control arm bushing.


Front:
- -------------------------------------------------
13.5.1 Front Suspension Struts

 section: Removing and Installing Front Suspension Struts
 
    5  The brake caliper bolts are torqued to 80-90 ft. lbs, and
       are a big PITA to get off, until you realize you should
       turn the steering so that you have enough room to use the
       breaker bar on them.  (I doubt you will be able to get
       them off with a regular ratchet.)

    6  Jacking up the opposite side makes getting the stabilizer
       bar off (and on) much easier.  Same applies for the rear. 

    7  You'll probably be needing the pickle fork set here.  
       This stumped me for a while, because I didn't know what a
       pickle fork was before I started this project!
       
       Also, if the boots aren't already split, using the pickle
       fork will probably do the job.  I think the boots are
       available individually, so you might look into this.

    8  I had to install the spring compressor while the strut
       was still in the car, to compress the spring slightly
       in order to get it out.  YMMV, because some cars have
       taller springs than others.  If you need to do this, BE
       CAREFUL, and don't compress the spring more than needed.
       The new springs went in without compressing.

  section: Removing and Installing Strut Bearing (Upper Mount)

    2  Use the adjustable wrench with teeth to grip the old
       shock absorber shaft.  (You probably don't want to do
       this if you aren't replacing the shock.)

  section: Replacing Front Strut Absorber Cartridges

    The threaded collar is torqued to 96 ft. lbs.  You will
       need some leverage to get it off.  I bolted the strut
       assembly to the wheel in order to get that leverage.  I
       think this is ok, because the hub should be designed to
       handle this lateral pressure.

    3  (see 0)


Rear:
- -------------------------------------------------
13.6.1 Shock Absorbers and Springs

 section: Removing and Installing Rear Coil Springs
 
    1  I needed to do this, but a friend with a 325es from the
       same year didn't.  YMMV.

    2  (see 1)

    Even though I lowered the exhaust and final drive, I still
       had to compress the springs slightly to get them out.
       I used the weight of the car to compress the spring,
       by putting a jack under the swing arm, and jacking it
       up.  I am sure this is against some shop safety rule,
       so you might not want to do it that way.  The new springs
       went in without needing compressing.

- -------------------------------------------------


I hope this helps someone who decides to try do their own
suspension work.  It is really not that hard, if you have the
needed tools, and leave yourself enough time.  It took me about
1.5 days, without air tools.

Now, go forth and lower thy car!


Rob Clark
San Diego
BMWCCA
'87 325is  (now low and stiff!)

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