...or, How to make your 325 "M-like"
I will start with the parts.
31 12 1 140 957 Left Control arm for 325 $72
31 12 1 140 958 Right Control arm for 325 $72
31 12 9 064 875 Offset control arm bushing set $40
31 35 1 090 268 Sway bar bushing for 25.5mm 325 bar $4 (need 2)
31 33 2 227 897 Left Upper strut bearing for M3 $80 (was sent the 96 model instead of the 95 I asked for)
31 33 2 227 898 Right Upper strut bearing for M3 $80 (was sent the 96 model instead of the 95 I asked for)
31 33 1 115 983 Washer $1 (need 2)
31 33 1 128 523 Front spring cushion $4 (need 2)
33 52 1 092 362 Rear shock mount $12 (need 2)
VE3-4237 Bilstein strut for 95 M3 $155
VE3-4238 Bilstein strut for 95 M3 $155
BE5-2453 Bilstein rear shock for M3 $101 (need 2)
29910 H&R spring set for 95 M3 $225 (comes with upper spring plates and cushions)
Assorted nuts and bolts $20
Bridgestone RE730 $474
Total parts
$1617
Total labor
$180 ($23/tire for mount, balance, disposal. $88 for "special" alignment...tweaked the camber)
Grand total
$1797
You can see my notes on why I went with these part in this thread:
http://forums.bimmerforums.com/forum...&threadid=2992
Installation
There were many more pictures that could have been taken (and I do have more, just not so interesting), but when things got tough, I tended to stay with the job and not take a break to grab the camera. Hopefully I have enough here to give some insight to the job.
I started with the front suspension.
Jacking from the center crossmember may not be an approved place, but it was the only way I had to be able to get two jackstands at the proper points under the doors.
Jacking the front
Once the car was securely on the jackstands, I went to work getting the old struts out. When removing the struts, make sure you support the hub/brake assembly.
Supporting the strut
As you can see, I made due with some soft rope. There are three bolts at the bottom of the strut that attach to the hub assembly. Two of these were very difficult to remove. They had some kind of locking compound on them, on top of which I could not get good leverage on the wrench. Once you have the bottom bolts out, you can remove the top three bolts that hold the strut to the car and pull the strut free.
With the strut out of the way, I started on the control arm. The control arm is held in place with two ball joints and a bushing at the rear. I started by removing the sway bar to have better access to the ball joints. The outer one is pretty easy to remove. Remove the nut at the top, and hammer in a tie rod remover (Sears, $15). The inner joint was a little more difficult. There was no way to get a socket on the nut without removing other parts on the engine. It is a 22mm locking nut, but fortunately a 7/8 open end wrench fit perfectly. It takes a while, but eventually it came off. Whacked it out with the tie rod remover after getting the nut off. The last part was to unbolt the bushing carrier, and the control arm is free.
I had to get the old bushing out of the carrier before installing the new one. I started by cutting the rubber away from the bushing leaving the metal sleeve in the carrier.
Bushing carrier
This is one of those places where more pictures would have been nice, but it was one of those struggling/cursing times that the camera stayed on the table. Once the carrier was free, I used a hacksaw to carefully cut the outside metal band of the bushing. I didn't want to touch the carrier with the saw since that would put a cut into it making a weak point. Cutting the band released the pressure holding the bushing sleeve in place, and it slipped right out. Putting the new bushing in was a chore since, as most people, I don't have a hydralic press at home. I made do with some spray lubricant and careful use of a bench vise. The bushing is a little wider than the carrier, so I used this tool behind the carrier and pushed it through so the bushing was even on both sides of the carrier.
Home made bushing tool
I could have made it out of wood and it would have been fine, but I didn't know what to expect so I made this up ahead of time to help with the bushing install. The bushing is 60mm in diameter, so the hole is 60.5mm and the press part (which I didn't really need) is 59.5.
The hard parts are done, it's mostly smooth sledding from here on. Here is a picture of the new control arm parts ready to be installed. Pushing the bushing onto the control arm takes some doing. The Bentley manual tells you to use a special lube, and then get the parts put back together and resting on the ground in 30 mins...not a chance. Not only did I not have the lube, but there was no way the car was going to be on its wheels in a half hour. I slobbered some Dawn (dishwashing soap) on the control arm and in the bushing, and pushed them together. It was tough, but it went on.
New control arm parts
I used the torque wrench where I could, but the inner ball joints could only get a wrench, so they got the "as tight as I can" treatment. They are locking nuts, and the ball joint is held with a taper so they should be fine. The taper, and the ball joint shaft must be clean or they won't stay together as well. When installed, here is what the new control arm bushings look like.
Control arms installed
After the control arms are in, I installed the new struts. Aren't Bilsteins just too sexy?
Bitchin yellow struts
The rest of the front is bolt-together. Got the wheels back on, moved the tools out of the way, and put my wife's car back in the garage. Quick shower to get some of the dirt off and crawled in bed at 2AM.
The next morning I tackled the rear. As I anticipated, this was much easier. Jack up the rear, and put the jackstands under the door spot again.
Jacking the rear
To get to the top of the shock, you have to pull the trunk liner away. I lowered the seat backs and pulled the side bolsters off. A good stiff yank at the top and they come off. There is a plastic cover across the opening that is held in place with some push-in fasteners. Remove this, and the fasteners holding the liner to the body, and you can see the top of the shock.
Accessing the shock tower nuts
I supported the rear control arm with the jack and removed the bottom shock bolt then released the jack letting the control arm hang. Remove the two shock tower nuts and the shock is free. Getting the spring out, and back in, is a little tough for one person. I was able to do it using a pole as a lever that I could push on with my leg while pulling the spring out. That was the hardest part of the rear install, but it was not too bad. The Bentley book wants you to remove the rear drive axles at the differential before doing this. Probably to avoid damaging the CV joints, or maybe just to make it easier. Hard to say if anything was damaged, but I think it is ok. Time will tell, maybe my next report will be how to replace rear CV joints
Once the spring is in place, just bolt the shock in, put the interior back together, and put the wheels on. Done!
I took ride height measurements before and after the install by measuring from the fender to the bottom of the wheel (not the ground...consult Bentley for how to do it). The rear is lower by .75" and the front only went down .5". I expected it to be quite a bit lower from it's old 325 self since I went with suspension components that were supposed to lower an M3 about .5" to .75" and the M3 should be lower than my 325 with the stock sport suspension. I like the rear where it is, but the front really should be lower. One possibility is the strut tower bearings. I had ordered a set for a 95 M3, but they sent me ones from the later model (96-99). I thought the only difference was the geometry, but it is possible that the height is different. I have to do a little investigating. Not sure what to do yet. It doesn't look terrible, but I would like it to be a little lower in front.
This morning I took the car to Roger Krause Racing for an alignment and to put the new tires on (Bridgestone RE730's 225/50-16). They did an excellent job and I left there with a straight steering wheel and tires that don't vibrate up to 110MPH
("professional" driver on a closed course). The ride is firm, but not uncomfortable. I have to let the tires break in before forming an opinion about them. So far they are a little noisier than the AVS Sports in the corners, and don't stick as well. They are quiet on the freeway though. We shall see. I did save $200 by using the Bridgestones over the Yokohamas so I can be consoled by this savings should they not turn out to handle as well.
Alignment specs:
Front
Left camber -0.8 deg, right camber -0.9 deg.
Left caster 7.2 deg, right caster 7.5 deg.
Left toe 0.07", right toe 0.06".
Some other numbers that I don't know what they are...
Rear
Left camber -1.8 deg, right camber -1.8 deg.
Left toe 0.10", right toe 0.10"
Thrust angle 0.00 deg.
Don't really know what to make of this except that the camber and caster are right there in M3 land, which is just what I was aiming for.
Sources
Zygmunt Motors
http://www.bimmerparts.com (most of the suspension components, best price on Bilsteins)
Turner Motorsports
http://www.turnermotorsports.com (H&R springs)
Double 02 Salvage, Hayward CA (local part resource, very nice guys)
Roger Krause Racing, Castro Valley CA (alignment, tire installation...excellent work, not inexpensive though)
What's left?
I am planning on an x-brace pretty soon, and now that I can attach the sway bar to the strut, I will make a link with some rod ends to do this. I could just buy the M3 links, but making them will be more fun. I expect that attaching the front sway bar to the shock will increase the rate enough that the rear will be too small, which means a new rear bar as well. My front bar is already larger than an M3 one, so I would have to go for an aftermarket one that is larger than an M3 to maintain a balance. But that is for future tweaking. Wheels would be nice, but that one will be in the distant future for now. I will post driving impressions once I get some stick time on the new tires and suspension.
I hope this gives you some idea what it takes to replace the suspension in an E36. It's not the hardest car-related work I have done, gutting an 88 Golf 16V and putting in a custom stereo, then putting it all back together was my peak. I could see myself paying the $400-$600 in labor if I were to do this again. I do have the satisfaction of saying I did it myself, and I had a great time, so all-in-all it was worth the pain
Have fun all!
Bernman
94 325is, M suspension (mostly)
*edit* fixed links to the pictures 12/27/03
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