Front end vibration

[pm179]

Hi All,

Speaking of front end problems, I have one I can't find. I have a vibration that shows itself at 75-85 MPH (no, slowing down is not a fix ;-)

If it is there at lower speeds I just don't know it.

I feel it in the steering wheel but it really shakes the whole car.

I've replaced tires, brakes, front upper & lower control arms w/ the nice bushings (sorry, can't remember the name). Each time I replaced these items I needed I was hopeful the shimmy would disappear, but it hasn't. It also remains in the same speed range

My mechanic insists it is still a rotating issue (tire balance) but he can't seem to get rid of it on his machine.

Any idea of the cause?

Thanks in advance,

Michael

[Mark_88_M5]

[pm179]

[Mark 88/M5 Houston]

rear and the problem was still there.

How many miles on the car?

Have any of the steering components been changed?

If it is a "rotational" problem I would think it would be there all the time and just increase and decrease in intensity with speed.

Have all the wheels been checked for "trueness", meaning are they round and do they have acceptable runout?

Some have had good luck with finding a shop with the Hunter 9XXX series balancers.

Just sort of thinking thru the keyboard.

[Gcracker]

Balance the tires/wheels in the front. Make sure the wheels are in fact true. Most seemingly impossible to resolve shimmy problems are related to damged wheels, and the damage is usually on the inside of the rim where you can't see it.

Another frequent fix that fails to fix, is buying new rotors, but going the cheap route with rotors that can't keep their true.

Finally, you didn't mention what condition your tie-rods and ball joints are in, not to mention idler arm bushings, etc. If they're loose, then any slight imbalance will be exacerbated.

I would definitely start with the wheels and tires.

[mike325i]

Mike, you can take your car to Ye Old Wheel Shop in Elkridge and they will check the wheels for true. They can also repair them if necessary but I don't know if they can do that same day. You'll have to call and ask them. (410)796-8400. Their address is 6363 Washington Blvd (Rt 1). Their shop hours are 8AM-5PM (M-F) and 9AM-1PM (Sat).

Mike
mike

BMWCCA National Capital Chapter
'88 M5 black/tan 5-spd 145k
'91 325i white/black 5-spd 220k
'91 318is red/black 5-spd 142k
'95 525i gray/tan auto/vanos 125k

[pm179]

Thanks Mike & all,

You answered my question before I could ask it. The wheels have definitely been rotated for tire wear, and they've been swapped with winter to summer tire change.

I was told tie rods and idler were fine but maybe I should go ahead and change them out anyway... nothing like throwing money at these things ;-) Will check wheels first, however, I'm the only one who drives the car and I haven't hit anything. So unless the wheels go out of true through wear I don't know if that is going to be my problem.

I'll keep all advised.

One more thought... I did buy a used drive shaft - could an unbalnced shaft send this type of vibration through the steering wheel?

Michael

oops -- nothing in the steering line has been replaced but I did have the box adjusted. Mechanic said it was loose??

[vze33jng]

'87 <b>528e</b> "is" 214.5k
'88 <b>M5</b> 193k (Head removed, ready for reassembly)
Dinan gen.1
OEM Front & Rear Fuzz-buster

[pm179]

[scottiesharpe]

Yes, a drive shaft which has sticky u-joints (they get depressions in the bearings on center) will vibrate and feel like a wobbly wheel. It normally gets worse as speed increases and is not noticable at low speed. However unlike a wheel wobble, drive shaft wobble will change with heavy acceleration / deceleration.

The idler arm is easy to check. It should move side to side, not up and down. Scottie Sharpe
84 745i 15 lbs boost, BMWTurboPerformance.com MAF kit, 17x9 3pc BBS, clean underwear, Executive Interior
88 Dinan-badged M5, M88 motor with 2 row conversion, Dinan Stage 4 suspention, Dinan 17x9.5 3pc wheels, 255/40 Conti Sport X 4, Racing Dynamics software, e34 rear brakes, B&B Stainless steel Exhaust, F&R LaDue stainless steel strut bars.
67 1602 Ireland coil overs, brembo brakes, Dual Weber 45
Do you BMWwikiwiki.com ??

[Michael in MD]

Guys,

I just got the call and found out all four wheels are bent! Two worse then the other 2... will be putting the "better 2" on the front with new tires. They will do the Road Force balancing and get as much vibration out of the wheel/tire as possible, but I cannot have them do the repairs right now (actually, at $100 per wheel it might be time to consider an upgrade from stock wheels)

Thanks to everyone for their help. Do you know that I don't remember hitting ANY kind of curb or hole that would have caused this. He said even hard cornering and 29 - 30 lbs air could cause this problem over time. Yes, I am surprised how easily they get warped/ bent ;-)

Regards,

Michael

[pm179]

Wow,

They balanced the tire/wheels very nice. Hardly any vibration at all even with the bent wheels (at least up to 90 mph which is past the 75-85 mph point the worse vibrations showed up previously)

Thanks again Mike, this is the first time in YEARS that it's been right. I've chased this dang thing round and round...

Michael