Intermittent Vibration

[BMWVW]

Hi all,

My car was not handling well, so I replaced the front tires and got an alignment. Now that the work has been done, the car handles like a charm with just one quirk. On certain roads or sometimes during acceleration and braking, I get vibration through the steering wheel and brake pedal. I went back to the mechanic (who has only done quality work for me in the past) and he rechecked the alignment, but I am not sure if he re-checked the balance of the front wheels. Even with the vibration, the car pulls straight, but the vibration can get bad especially when you only have one hand on the wheel... yes, defensive driving would have me place two hands on the wheel at all times . He mentioned that maybe a part in the steering mechanism may have worn out (sorry... can't remember what he called it). Just wanted to see if anyone had any thoughts before I talk to him again. To me it seems like it might be the balance on the front wheels, but I don't want to bug them again if no-one agrees! Could the balance on the rear wheels cause a problem like this?

Cheers,
Paul.

[Tyler]

I'd say your ball joints are bad. How is the wear on the front tires? Is it wearing out on the inside of the tire?

[BMWVW]

Thanks Tyler. New tires on the front, so I don't know yet for sure and the old tires for so messed up that I won't want to base anything on those tires!

So ball joints... any other ideas/comments?

Cheers, Paul.

[aceyx]

i've had this same issue resolved with simple balancing.

having that checked shouldn't cost a dime.

[msi]

I am having same problem. Spent about $500 on various inspections etc but no luck. i have narrowed it down to problem related to brakes. Sometimes, when I get in the car in the morning, brake paddle depresses all the way in and after pumping it few times, it is fine. There is no air in the system. (checked it, had it checked 2 times) No brake fluid leakage or loss.

No warning lights.

Is there any connection with vacuum hoses and how do I check that?

Thanks

[BMWVW]

So, it turns out that the major vibration was caused by worn out control arm bushings. With those replaced, the vibration is better, but not total gone.

Now that is the thing that is confusing; even with the bushings replaced, there is still vibration. It feels more dampened and less violent than before, but it is still there. The mechanic checked everything around the steering and from what he can see, it is all solid. The balance on the front wheels is fine.

One other thing I noticed this last week, is that it seems that the whole car is vibrating at certain times. Very gently, but noticable. The car is still handling well, but the vibration is starting to get frustrating and I am concerned that it is a sign of something needing repair and I would like to fix it before it wears down other parts or causes other damage.

Any suggestions would be appreciated.

Cheers, Paul.

[BMWVW]

Actually, one other addition: The vibration seems to be above 50-55mph only. That makes me think it is the balancing of the wheels, but they have checked it twice. I trust my mechanic and his work, but he has admitted that he cannot think of what would be causing it.

I am only going to on the summer wheels for another 1 - 1.5 months, so I am thinking I might wait till my winter wheels are on and see if the vibration stops. At least that way, I should now if it is related to the wheels or not I suppose. Would anyone recommend still getting another balancing done prior to getting my winter wheels on?

Cheers, Paul.

[Matt-UK]

I get the exact same thing, but between 40-50mph. I think theres a few other people who have this problem here.

[JPerfect]

I had that problem, I had my control arms, bushings, and ball joints replaced, then after an alignment, all was dandy. You might want to check out your tie rods as well.

BUT BEFORE YOU DO ANYTHING

Make sure all of your lugnuts are tight. Loosen them, and tighten them back up. It's possible a wheel may have slightly loosened and settled. That happened to me on the NJ Turnpike on my way to Belmar, and I thought my engine was going to fall out of my car. Upon inspection at a rest stop, I noticed it had nothing to do with the engine, it was a few loose lugnuts... not only were they loose, but i think in a few more miles, my front right rotor would have left a gash in the asphault as I spun into the divider. I think i spun one of the nuts three times with my fingertips and it came off in my hand.

-Jeff

[BMWVW]

Definitely something simple I can check. I was thinking of that this morning, but I was late for work and it was pissing down with rain. I will double-check before I leave work.

One BMW mechanic still thinks it is the wheel balancing or the wheel is bent. He stated that the BMW front end is very sensative to vibration and will respond quickly to even the smallest vibration in the wheels. My mechanic is going to check the wheels again tomorrow. I have hit one or two bad pot holes that I couldn't dodge in time, so it may even be a bent wheel. I hope not though

Cheers, Paul.

[BMWVW]

One more update...

so I checked the lug nuts and they are nice and tight. My mechanic offered to check the balance on the wheels again as he had asked a collegue to double-check them the last time. They were still a little out of balance so he fixed them. While there is a bit of vibration, it starts at about 70mph rather than 55mph now. Feels much better.

Their machine is a light weight model so they can take it to the track and it is good to about 1/10 oz. So I might take the whees for a re-balance next spring (I might paint them this winter) and find somewhere with a more precise machine.

I feel better that it was the balance though as I didn't really want to fork out a load for suspension!

Thanks for all the input.

Cheers, Paul.

[msi]

Narrowed down the problem to the front brakes. Brake pads were not releasing sufficiently. You might notice slight drop in the brake fluid level. Also opverheating. Mechanic insisted that the calipers are the problem. Changed them. Problem has reduced considerably but is still there. Next step is to change the ASC relay (cheaper option and then look at the master cylinder.

Any thoughts / suggestions are welcome.

[DeadpaN]

you might want to try a bushing/piston repair kit for the calipers. they could be worn or dirty.

[aceyx]

BMWVW; after looking at your location, two things you might want to get checked out: the guibo (flex joint) and wheel bearings. The latter is generally worse when the car is cold, and when turning in one direction. I figure they salt heavily up there, so your guibo might be a bit decayed.
I can't say I've had much a problem with the front end oversensitive to non-straight wheels, as I used to live in Boston and never reallly noticed it that much.
Also check to see that the lug_bolts_ are torqued correctly. Overtorquing can lead to rotor warpage, which could push the wheels off the hub in a strange manner.
How many miles on the car?

msi; you may want to check torque as well. I'm pretty sure that ASC only affects the rear wheels, and that only retards the ignition, so it would be a jolting feel or a loss of power, rather than a wobbling (yes, I'm rather technical).
Do you still want to know about the vacuum lines? All disc-brake systems have a "booster," or power assist that runs off the vacuum from the engine. I'll have to look to see where it is on our cars, but it should be right before the brake lines split.

[scottrt]

You may have a tire that is slightly out of round. In my 25 years of of bimmers I have found them very sensative to this. I have bought dozens of sets of tires in the past few years and the odds of getting an out of round one is suprisingly high.....Michelin, Dunlop, Yoko, Bridgestone.... they have all had issues. You need a to have the tires put on a balancer/trueing combo machine. You will be amazed. I have all my Bimmer and Mini cooper tires checked for true. QC in this area in crappy considering how sensative modern front susps. are,,especially Bimmers.

Scott T.