In October 2004, I bought a 1990 535iA as a project. I’d always wanted an e34, looked at a few 525’s and 540’s, but decided that it had to be a 535. “Fritz”, as I later named the car, had sat in someone’s back yard in North Carolina for about two years. When I bought the car, I was told that it needed a few things: the transmission computer needed re-programming as it had no reverse, it had a lot of dents with bad paint, and it needed new struts, strut housings, and upper/lower control arms. Between November 2004 and February 2005, I spent about $4000 and countless hours of my time restoring the mechanical aspects.

Shocks & Springs

When I first bought the car, I knew little about suspension options available for the e34. I knew that I had to replace my shocks and strut housings, so I figured I’d replace the springs as well. I was lucky enough to find two used strut housings on eBay for $80 shipped, which included installed shocks and stock springs. I’d heard of Bavarian Automotive and bought their “sport” lowering springs on sale. At that time, I was trying to do everything as cheaply as possible: I also bought a set of KYB gas shocks for the BavAuto springs. However, I ended up returning the KYB’s in favor of running the old struts on the rear and the inserts in the replacement strut housings.

My initial impressions of the BavAuto springs were favorable; perhaps this was because I’d replaced every other front-end component (thrust arms, control arms, all steering links and idler arm). Additionally, the BavAuto springs SLAM the front end, making the car look great in the front. Two things started to bother me: the rear camber was unsightly - the stock 15” style 5’s were visibly slanted and sat high up in the wheel wells (see pic); as well, running over bumps or turning into my driveway became an exercise of caution. The most unsettling fact was that the front alignment indicated that one shock was weaker than the other, meaning that the steering wheel had to be at an unnatural angle to travel in a straight line. Time to do the job the right way.

BavAuto springs on old struts – December 2004

Prep Work

In committing myself to doing the job the right way the second time around, I started listening to my acquaintances on Bimmer.info, who raved about a company called “BMA” and their $650 deal on the so called Sachs Kit. After working with Patrick at BMA to solve a number of cooling system problems, I decided to order the kit. I thought about a Vogtland/Koni setup, but availability limited that prospect. As well, I considered the Bilstein sport and H&R/Eibachs combos, but read that the Bilstein is not a comfortable strut to put on this car. As I plan on doing a lot of ‘Bahning in the coming years, I elected to use the e34 tuned Sachs product:

It includes: (4) lowering springs (made by Eibach), (4) Sachs labeled Boge turbo gas struts, (2) strut housing collar nuts, (2) 22mm sheaths (for fitting the front inserts into 22mm strut mounts), (2) rear strut spring pans, (2) front modified bump stops, (1) set of poorly written instructions and hilariously complex letters from the TUV in German.

In addition to the standard kit, I ordered a set of new rear bump stops. You also want to get a set of REAR strut mounts – DON’T BUY MEYLE…ever! (they use substandard plastics in their products that will fail earlier than most) If your car has >120k on it, I would also recommend ordering new front strut mounts. Finally: you may want to get new plastic dust shields all around; I decided to reuse mine, although I had to clean them up a bit.

Here’s a comparison of the stock springs and the new Sachs Eibachs:

Note how much shorter the Sachs front is versus the stock; Interestingly, the rears are about the same height, although this is no indication of how it will ride, which is more dependent on tensile strength and spring rates.

One of the things to do prior to the install is to adjust the rear spring height setting. Sachs recommends that you use the “upper” setting for street use. I’m using it because I want to prevent having too much negative camber. Here’s a picture of the insert on the “upper” setting:

I used my fingers to move it and it took a few minutes; a pair of needle nose pliers would dispatch it in a few seconds.

Necessary tools and materials

I’d used a well-stocked garage to install the BavAuto springs. Although I knew that an impact wrench would make my life easier, I don’t think it’s necessary (as it turned out, one WAS necessary – but that was my fault for previously over-torquing bolts). I used, more or less, the following tools (generalizations have been made because there are minute differences between the model years and aftermarket/replacement parts that sometimes are an odd size):

• Complete set of metric sockets – from 10mm to 24mm
• Set of combination/box end metric wrenches – from ~10mm to 24mm
• Hex keys – 5mm - 8mm, 9/10mm(?) (ABS sensors, brake caliper mounting bolts, rotor mounting bolt, tightening the new strut nut)
• A good spring compressor: build, buy, or rent one from AutoZone or NAPA
• Breaker bar and a few good extensions
• A 1’ large monkey wrench (to remove strut housing collar nut)
• Smaller flat head screwdriver
• Some strong wire, such as a coat hanger, to support the brake calipers
• Two good jack stands, a quality jack, and a set of ramps (or two old tires)
• Threadlocker: Red Loctite
• Rust/surface tension removing catalyst: PB Blaster
• Important: 12 new self locking 13mm nuts for mounting the struts
• Optional: I use a lot of anti-seize grease when I put everything back together because, let me tell you, separating fused hubs/rotors/wheels is not fun.

The Install - Fronts

1) Jack up and properly support the front of the car. I place the jack stands under the frame members. Remove the front wheel(s)

2) First things first: lift up the dust cover and saturate the strut housing collar nut with PB Blaster. I do both sides at this point to give it time to soak while I disassemble the other parts. If you’ve got a rust belt car and don’t work on the bolts often, better spray all of the bolts first:

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