Hey team. Need a little help diagnosing a problem with my E36 suspension.
Been doing some reading, found a few issues similar to mine, but none that replicate it.
I'm experiencing rear end instability at highway speeds. It feels like an excessive cross wind, or like a trailer starting to get the death wobbles on.
I had my alignment checked this morning, and nothing was out of the ordinary.
Recently i redid my rear subframe, replaced all subframe, diff and trailing arm bushes with power flex poly bushes, installed adjustable camber arms with a pillow ball bearing on the inside. The spring perch inner and outer bushes are still the original rubber, as are the camber arm outer bushings. I plan on replacing these next with the upgraded M3 bushes.
Anyway, my question is:, I installed some delrin rear trailing arm limiters WITH the polyurethane bushes. Is there the possibility that what I'm feeling, rather than being movement caused by a less than ideal alignment, is in fact just the standard movement from highway driving, that would normally be absorbed by rubber bushes. IE I actually have a more responsive car, but one that is just really twitchy.
The problem is always more noticeable when passing, or being passed by a truck (obviously the bow wave is moving the car around somewhat)
Im happy to live with the problem, as the car doesn't see much highway driving, primarily being driven to and from the track, and with the current setup corners really well (hasn't actually been track tested yet, but that is coming soon.
FWIW, I'm running KW coil overs, with the front pretty stiff, and rear not adjustable, offset front control arm bushes, and offset M3 front strut mounts. i have 235/45/17 tyres, Kumhos on the front and Toyos on the rear - nothing special about them.
Cheers guys
I have experienced the exact symptoms on a stock Nissan Sentra, years ago. Found out it was caused by mismatched tires, or tire tread patterns. Problem disappeared, once I installed a complete set of new tires. Not sure if this is the cause of your problem, but your statement on mismatched tires, front & rear, caused me to comment on my experience with them.
were you having that issue before you had all the same tires? or is the mismatching tires? like Mikyzz4 says?
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Thanks for the reply, this didn't occur to me at all. I've driven with mismatched tyres for a while. I always assumed if they were the same on the front axle and the same on the rear axle it wasn't an issue. If i cant solve the problem, ill definitely play with this.
I echo mid-matched tires.
Stiff suspension retaining rear outer upright non-M rubber isolated bearing/bushings can cause some 'loose' feel.
However this also sounds like rear toe or cross toe issue similar to what I had recently. Corrected with alignment.
FYI- The combo of 1996+ front bearing plates and offset LCA bushing makes steering really slow. This combo can also lead to rubbing issues.
The spring perch outer bushing is actually a bearing, and if still original with high mileage likely worn and contributing. Replace both the outer upper and lower hub bearings that the control arms attach to and that should tighten it up.
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2004 M3 convert 6sp man - low mileage beauty!
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