Vibration Problem

**FrankA6** · 08-22-2008 04:47 AM

I have a 2004 A6 S-Line, on Koni FSD and Eibach springs, and iam running 18x9 35ET Raderwerks Mten-80's all around with 235/40/18 falken ziex 912 tires, and for some reason, they just wont balance, i have had them done 3 times now, and a rear axle changed, the car aligned 2 times, but not since the new wheels have been on, and it still vibrates very bad from 55-75 mph, and i have hubcentric rings, and cone tuner bolts, all the correct stuff, ive had 2 garages tell me that one of the rear tires has a defect, but it still vibrates bad in the front and back, could it be the tires, or tie rod or somthing, let me know what you think? get new tires and get the car aligned? - thanks.

**old guy** · 08-29-2008 08:05 PM

Originally Posted by FrankA6

I have a 2004 A6 S-Line, on Koni FSD and Eibach springs, and iam running 18x9 35ET Raderwerks Mten-80's all around with 235/40/18 falken ziex 912 tires, and for some reason, they just wont balance, i have had them done 3 times now, and a rear axle changed, the car aligned 2 times, but not since the new wheels have been on, and it still vibrates very bad from 55-75 mph, and i have hubcentric rings, and cone tuner bolts, all the correct stuff, ive had 2 garages tell me that one of the rear tires has a defect, but it still vibrates bad in the front and back, could it be the tires, or tie rod or somthing, let me know what you think? get new tires and get the car aligned? - thanks.

See if you can find a shop that uses a Hunter Roadforce balancer. I have had good luck with this type of balance where others didn't work. Clicky click The Roadforce system can identify a faulty tire (soft spots, constructional variations, etc) that a conventional balancer won't show up.

Edit: Just to show you where I am coming from: Clicky click

**Doc@tirerack** · 09-02-2008 02:06 PM

We work with Westover Auto on Holland Ave in Morgantown, and they have the Hunter Road Force machines in house.

**2.7tDallas/JonD** · 10-17-2008 08:29 PM

I have H&R and FSD, with velocity 18x8.5 and RE750's, and I have exactly the same problem on my 2003 A6.

I just had all the control arms and TRE's done when I had the shocks put on, and did teh wheels at the same time

I wonder if the FSD's are doing something strange

**kastro** · 10-17-2008 08:34 PM

i have fsd no problems at all.. i go 150km/hr with no vibration what so wever.. just shitty tire noise...um.. ya.. id try the gsp hunter machine.. they use laser allingning thats what i did.. . dumb question and thread jack a bit.. If my differential was fucked or stressed.. what would be the symptoms.. my car was in an accident and they didnt flat bed it off the road.. still getting repaired but just wondering.. tahnks.

**belinko** · 10-18-2008 02:51 PM

I'm running a 235/40/18 +37 offset and have had some vibration issues.

When the tires and wheels where 1st mounted everything was perfect. I recently had the wheel/tires rotated front to back and this is when I got a significant amount of vibration in the steering wheel. After rebalancing and messing around with the wheels I've determined that the hubcentric rings for my wheels don't fight tight enough between the hub and wheel. Thus everytime the wheel was unmounted, it never went back into the same concentric position. My current hubcentric rings are made of ABS (Plastic) and I will be purchasing Graphite ones and/or Aluminum ones as they hold there shape and tolerances better under heat cycling. At $20-$50 for a set four, I think they're worth replacing for every set of tires.

If you're running hubcentric rings measure the ID of the wheel and OD of the hub and ensure that the hubcentric ring matches the ID and OD dimensions ±.05mm. This tolerance range should eliminate the vibrations.

Audi Hub is usually Ø57.10 mm ±.05mm

**2.7tDallas/JonD** · 10-18-2008 06:36 PM

Great idea, but the Velocity RS4 reps I have do not use Hub Rings

**Peter@VMRWheels** · 10-18-2008 08:33 PM

Originally Posted by 2.7tDallas/JonD

Great idea, but the Velocity RS4 reps I have do not use Hub Rings

Try balancing the wheels/tires, and if the vibration still happens, you've basically eliminated the possibility that it is coming from the wheels or tires.