Few Problems With My 89' 635 CSi

[BimmerPdx]

Hello All,

I recently purchased my first CSi and it has a couple problems. Firstly, the steering shakes between 75-80 MPH. I had this problem on my 94 530i and also with my 98 325is and on both cars I ran through tie rods, wheel bearings, control arms, and steering columns trying to pin point what the problem might be with no luck. On the CSi I think it might be that the wheels are off balance because the wheels don't move side to side when it is lifted off the ground and I don't feel any "loss of control" when I am driving it. This being my 8th older Bimmer I have a gut feeling that it is something more then all that, it seems to simple. Any help would be appreciated.

Secondly the rear hydraulic shocks are blown. I already planned on taking out the original suspension and putting in aftermarket parts. Was hoping for any good recommendations for good ones to use.

Thank you all for your help.

[Nullified]

Have you tried driving with a set of wheels that have been confirmed true? If no shudder reveals itself you found the source.

[bkats]

I have an '89 that had a similar problem. The suspension was good, so my mechanic just loosened everything in the steering column and re-tightened in some specific order he deemed "correct" and it was solved. Apparently this was a trick he learned when he was a tech at a dealer.

For the rear shocks, I just used the non-SLS shocks for the model and have loved the results. I considered lowering the whole car when I replaced them, but I have 17's, so I decided against it. The wheel gap doesn't bother me.

[SprCpe]

I had a similar problem with my 89, BBS 1 piece style 5's and new suspension. It took the tire store three tries to get the shaking out, just really temperamental suspension I guess, but it runs nice now up to as fast as I want to go.

The PO of mine deleted the self leveling suspension and dropped in older 85 or 86 rear shocks and springs from an old car, shocks were shot so I went through and replaced everything, Bilstein sports front and rear and H&R sport springs, bigger sway bars, it sits about 1.5 inch's lower, ride is stiff :-) kind of hard in town, but I still enjoy it on the road.

[DesktopDave]

I had a similar vibrating problem in my '89 525i, got lucky solving it. Thrust bushings were worn and the steering shaft gland nut in the cabin was loose. These cars are infamous with those front suspension problems. The E24 has another specific problem - the steering rack subframe welds can fail at higher mileage. Check the side bolt 'ear' for cracking on the subframe. There is a hobbyist that makes reinforcing kits with a bolt & tapered bushing but I couldn't find it. Here's some details about a complete weld-in repair.

I've always swapped Bilstein Sports onto my Bimmers. I tend to like the sportiness of them, but they are a little harsh & busy for in-town driving. The stock Sachs units aren't bad at all. I'd recommend replacing all the rubber bits (rear subframe biscuits, dogbones, sway bar bushings, upper shock bushings, spring isolator pads, RTABs, diff mount) with OEM BMW parts while you're in there. I know it's expensive but IMHO worth not going in again.

[BimmerPdx]

Thank you everyone for the help. I'm gonna start off on the cheaper end and try the tires first this time, if not ill work my way to the sub frame steering rack and all the accoutrements involved. Desktop Dave- I was unaware that this model has 'infamous' suspension problems, so thank you for informing me of that. this is the first I am reading of any of it.