Vibration...Is it my wheel bearings?

[Gujuhammer]

Back story: Took a 4hr ride down to SW Indiana and I felt intermittent, strong vibration in my steering wheel at ~50mph. So I went to get the wheels rebalance and found out that my two front wheels had slight bends in them...Got them straightened and refinished at Wheels of America, mounted the tires, and rebalanced the wheels. I have Porsche Cayenne BBK, H&R 5mm spacers, B6 S4 Avus wheels, Tires are BN (<3k on them), replaced the control arms earlier in the year but I've haven't (never) replaced the wheel bearings (98k on the car).

Now: I still have intermittent vibration at highway speeds but it's not nearly as strong as once was...Is it the front wheels bearings? How do you know when you need to replace them? Could it be something else?

Any help would greatly be appreciated. Thanks guys.

[Gujuhammer]

Bump.

[odhinnhrafn]

If they're going out, you should hear them humming, usually pretty loud. Did you replace your tie rod ends with your control arms? Another possibility. To test the wheel bearings, put the car in the air, tires off the ground. Grab the tire, and try to move it back and forth. If it moves, good bet your bearing's on its last leg.

[Gujuhammer]

If they're going out, you should hear them humming, usually pretty loud. Did you replace your tie rod ends with your control arms? Another possibility. To test the wheel bearings, put the car in the air, tires off the ground. Grab the tire, and try to move it back and forth. If it moves, good bet your bearing's on its last leg.

I did replace the tie rods at the same time as the control arms. I haven't heard any loud humming or weird noises, but I'll check the wheels when I get home from work.

The vibration isn't horrible, it's intermittent, and goes away when I accelerate...Any other ideas of what it might be?

Thanks for the help.

[odhinnhrafn]

If it goes away when you accelerate, more likely to be your engine and/or transmission mounts.

[Gujuhammer]

If it goes away when you accelerate, more likely to be your engine and/or transmission mounts.

That's not good...

[odhinnhrafn]

Tranny mounts are easy... Engine mounts a bit harder, but not impossible. Not horribly expensive either.

[Gujuhammer]

I see a lot of guys getting the Stern motor mounts over the RS4 ones...Is there a big difference?

[ezfour]

I see a lot of guys getting the Stern motor mounts over the RS4 ones...Is there a big difference?

Yes, RS4 are hydraulic, Sterns and 034 are solid high durometer rubber. If I could do it again I would go with Stern track motor and trans mounts or if 034 the track motor and street trans mounts. You dont want to transfer too much vibration through your transmission. Dont forget about the snub mount, 034 makes a good one, and Apikol or Stern rear diff mounts.

[Gujuhammer]

Checked the wheels and it isn't the bearings. The car tracks perfectly but the vibration keeps coming and going...I only feel it in the steering wheel. Could it be something in the steering rack?

I think I'm going to go with the 034 street trans mounts but I'm still not sure about the motor mounts. Like you said I don't want a lot of vibration, plus my car never sees the track.

[wagstach]

sounds like something to do with your steering rack/ tie rods

[99blueb5]

most likely one of your mounts of your center driveshaft bearing going out

[Gujuhammer]

sounds like something to do with your steering rack/ tie rods

Tie-rods were replaced with the rest of the control arms.

[Gujuhammer]

most likely one of your mounts of your center driveshaft bearing going out

Makes sense, but I have no idea what this involves...Anyone have any pictures?

Thanks for all the help boys.

[Gujuhammer]

UPDATE So I did some searching in the forum and found out there is another way to balance your tires. Road force balancing with a Hunter GSP9700. Here's the web site: http://www.gsp9700.com/index.htm to find a location near you. 3rd time getting the wheels balanced was the charm. It solved most of my vibration problem but my tires are a little "feathered" due to the previously imbalanced wheels. Don't make the same mistake I did and get your wheels "spun" balanced. I have to say that I feel pretty dumb/embarrassed after I figured all of this out but I am glad that I did.

Appreciated the help from everyone and I hope this helps a fellow member out there.

[audigeorge1]

Back story: Took a 4hr ride down to SW Indiana and I felt intermittent, strong vibration in my steering wheel at ~50mph. So I went to get the wheels rebalance and found out that my two front wheels had slight bends in them...Got them straightened and refinished at Wheels of America, mounted the tires, and rebalanced the wheels. I have Porsche Cayenne BBK, H&R 5mm spacers, B6 S4 Avus wheels, Tires are BN (<3k on them), replaced the control arms earlier in the year but I've haven't (never) replaced the wheel bearings (98k on the car).

Now: I still have intermittent vibration at highway speeds but it's not nearly as strong as once was...Is it the front wheels bearings? How do you know when you need to replace them? Could it be something else?

Any help would greatly be appreciated. Thanks guys.

I had the same issue it turned out to be the inner tie rods! I also chnged my hub bearing because i had the loud humming noise as well. But for sure the inner tie rod will cause vibration in the wheel!

[twiztids4]

you probably are getting some vibrations due to your wheel spacers. Try taking yours off and see if it changes anything...

[s4playr]

I had a decent amount of vibration around 50-60,, when I did my timing belt, the kit I bought came with a new snub mount,, made a HUGE difference.. I had no idea that really could make such an amazing change :)

[dubzackvr6]

UPDATE Road force balancing with a Hunter GSP9700. Here's the web site: http://www.gsp9700.com/index.htm Don't make the same mistake I did and get your wheels "spun" balanced. I have to say that I feel pretty dumb/embarrassed after I figured all of this out but I am glad that I did.

Appreciated the help from everyone and I hope this helps a fellow member out there.

Thanks for the link. Definitely good to hear it was a simple fix.

Just a thought: center driveshaft vibrations aren't felt through the steering wheel most of the time. More of a seat of the pants vibration.

[Gujuhammer]

Thanks for the link. Definitely good to hear it was a simple fix.

Just a thought: center driveshaft vibrations aren't felt through the steering wheel most of the time. More of a seat of the pants vibration.

You're suggestion made me do some research on engine mounts, trans mounts and all the components of the drive shaft. At the very least I got a little more educated about the car, which is always a positive in my book.

[ECS Tuning-Audi]

Road force balancing is always the way to go! The wheel reacts completely different when its loaded up rather than just freely spinning.

Jason

[Highhats]

You could be getting a harmonic sound from the tires. I had this happen. Audis are notorious for cupping tires even with perfect alignment intervals. I shaved my front tires to make them smooth again (25 bucks a tire) and the sound was gone. I too thought it was a wheel bearing and walll ahhhh!

[Gujuhammer]

You could be getting a harmonic sound from the tires. I had this happen. Audis are notorious for cupping tires even with perfect alignment intervals.

Is this because we can't adjust the camber? I'm plan on keep this car for the rest of my life (fingers crossed), so should I be setting aside $500-$600 for a set of adjustable control arms?

Thanks again for the link Highhats.

[quickdub]

adjustable arms are a must if you're lowered more than an inch in my opinion... I have adjustable arms in the front & rear upper locations and makes a huge difference in tire life and handling.

Suffering from vibrations above 40 mph in my car. Gonna try Road Force Balance and see if that helps. Just installed an Apikol rear diff mount, which amplified the problem in my case.
Didn't change the 2 bushings at the back of the diff yet, but they didn't look torn.
I think it might be CV joints in my case, since I had this issue when i changed the ride height on the vehicle about 5 years ago. I replaced rear CV's and wheel bearings and the problem went away. Seems like the CV's wear in certain pattern, and when you change ride height they ride in a different part of the race, and start making vibrations. So I plan to start there, and work my way in.

I still have a few other things to check, since my car was involved in a minor accident a few months ago. I will be replacing my hubs with the new bearings, so it will eliminate that as the possible culprit... But before I do all that, I will take your advice and get my wheels re-balanced. I never felt this thing roll smoother, than after I had balanced the wheels last year on one of these Road balancing machines. Very good for low profile tires and large wheels. Solved my problem the last time I was having vibrations up front. I think my BBS wheels are a soft casting, and they lose balance every once in a while. Also, as your tires wear the balance changes, especially if they're wearing unevenly.