ColoQuattro

I have posted on this topic before and this is a update of sorts.
Have purchased Ronal R-38 18" wheels (really pretty) and Mich Pilot A/S 18' (p245/45/18) tires. Have a substantial steering wheel ossillation at 52-55 mph. Have switched tires from front to back with no difference. Road force balanced tires and wheels and no difference. Put stock P-6's back on car and ossillation goes away.
Discount Tire is very accomodating and has been trying to resolve the issue. Discount tire is talking about replacing tires with another brand of my choice. Found one Ronal out of round and replaced it with a new wheel. The Ronal's have a TUV approved spacer/hubcentric ring system to fit the allroad.
Questions:
1) What are the chances of the ossillation problem being due to the spacer/hubcentric ring system? The tires and wheels run straight and true on the balancer and zero out to no more than an ounce of weight on one tire/wheel and .5 on the other three! They osslilate the steering wheel like crazy when on the car.
2) What are the chances of the ossillation being due to the A/S Michellin's? What if I went to a 17" Ronal Michellin A/S wheel/tire instead of the 18's.
3) If it is the wheels what other manufacturer's make a wheel to fit the allroad without spacers or rings that have 10 spokes? Where can I get a set of new Audi RS4 wheels other than at the dealer that do not have spacers or rings?
5) If it is the tires what other tires would be recommended as being as good of a riding tire, without quality issues and noisey operation. Regular Mich Pilots? P zero Pirelli's, Dunlpo's, Bridgestone's, Yok's?
I am pretty well stumped...any advice will be appreciated!!!!

03Indigo

If not, you can try and put mine on and see if the problem goes away...without spacers on...then procede by putting on spacers with OEM wheels, if the problem starts, could be the spacers, if not, then maybe the wheels/tires you have are causing the problem. Let me know if you want to come by some evening and we can switch out tires and stuff, I have an air compressor, so it makes an easy job of changing tires.

cheers
jon

paulroad

a miss-mounting when you put them on the car.

I would think the probelem comes in to play when you mount to the front. How about continuing your proecess of elimination...

Put 18's on rear only... test drive... if there is no vibration... put ONE wheel on the LEFT front.. I know 17/18 missmatch.. but for a breif drive you are ok. If you have vibe then look at the mating between the spacer and the wheel and the space to the rotor. If you have the vibe...then change spacers. If you still have the vibe.. then change the wheel.

If you have no vibe on this rotor match.. then do the same process on the right side.

I know its time consuming and tiring.

I think that eith Acthtuning or perhaps Hartmann have RS4 replicas that are specific to the ar..no spacers needed.

Good luck

allroad'Ed now

with a slightly different twist than Paul's suggestion.

I went through this myself. Mounted all 4 stock wheels and tires. Then one at a time I mounted the aftermarket wheels until the problem came back. Was able to isolate the problem to one wheel/tire combo. Re-road forced that unit and found the tire to be out by 25 pounds! Replaced under warranty.

Good luck.

allroad'Ed now

1) What size spacer did Gary send you with the Ronals? Could be that you have too much offset from too thick a spacer which might affect the "scrub radius" of the car. If you space the wheel out too far from the original configuration, the centerline of the wheel goes beyond the designed parameters of the suspension and can cause issues. If you have room between the back of the tire and the struts, you might want to try thinner spacers.

2) The problem with the Sport A/S tires seems to be that they are a very low rolling resistance tire. So there is less parasitic drag when the tire is rolling. This, according to Michelin, accentuates whatever problems may already exist in the car. So I'd have a hard time believing that this by itself is causing your problem. But who knows. What was the RoadFroce reading when they spun them? I believe that Spec says less than 12 lbs out is OK but on our cars could cause a vibration.

3) Saved the best for last. How did they balance them? With the spacers installed in the wheels??? And did they put the machine's centering cone in from the front or the back? Very common that the tire guy wants to just put the wheel flat onto the machine, put the metal cone in from the front and then spin on the big bolt that holds the wheel in place. This won't work well.
The wheel is only machined for the center bore from the BACK.
The cone should be put in from the back of the wheel to simulate the hub of the car. Most shops don't like this because the front attaching device will not be against the face of the wheel and runs the risk of scratching if not done carefully. But it won't work properly any othe way.
As far as the spacers installed. If the wheel/tire was not balanced with the spacers in place, how do you know if the spacer itself is warped or improperly machined? Or even out of balance? Can either retry balancing with the spacers in place or ask Ronal to send you 4 more spacers to try.

You should be able to make it all go away. Just some tiral and error.

blackfrd

Each time I hear a story about wheel/spacer vibes, it makes me less inclined to go that route, but I'm still planning on it. There obviously are combos that work.
Question, are your spacers both hubcentric and wheelcentric? When you mount the spacer only (no bolts), to the hub, is there any play at all when it is pushed up/down and forward/aft? If yes junk the spacer.
When you mount the wheel/spacer combo to the hub (no bolts) is there any play? If yes junk the spacer.
If there is no play you could check for runout of the spacer cone when installed on the hub. Not a hard thing to do if a micrometer and fixturing is available, not so easy if you have to round the stuff up. May be the tire store is set up for this. If you can check runout, also check the face of the spacer, and also the hub and face of the axle flange (for reference). I don't know what the factory specs are, but there should be very little runout. May someone can help with specs. You will also have to use washers or similar on the bolts to fasten the spacer tightly to the hub. If the spacer runout is more than the axle runout, you have a bad spacer.
Please keep us posted, I am very interested in the outcome.
Good luck.

allroad'Ed now

Ronal's spacers are hubcentric to the car's hub then centric to the back of the wheel, even held in place with snap rings. All TUV approved.

But as I mentioned in my post below, could still be a poorly machined spacer.

ShowMeData

I think you'd have to have the tire guy do the RFB with and without the spacer, if you're trying to verify the spacer. If they're not explicitly suspect, I'd leave them off. Balancing with them in the system is adding some random variability which reduces your ability to perfectly balance the wheel/tire combo (unless said spacers bolt to the wheel, and you could perfectly reproduce the alignment of the wheel and spacer when reinstalling to the car).

FWIW, I'm not familiar with the specific machinery used for RFB (it sounds like you are), just happen to have some experience with precision balancing other rotating systems.

allroad'Ed now

If they've been balancing the wheel/tire assembly without the spacer and everything looks perfect, then I would suspect the spacers next. Process of elimination.

FWIW- the first set of H&R spacers I got caused a shake. As I looked at them, one looked odd. All H&R's for Audis come drilled with both 5x112 and 5x100 bolt patterns to cover VW and Audi. Turns out that only 4 of the 5 5x100 holes had been drilled out causing an imbalance. Bizarre! But true.

If I were coloQuattro, I'd call Ronal and ask them to send a new set of spacers/ centering rings to try.

ColoQuattro

The rings are the snap in TUV type and are tight to the wheel. They also make for a tight fit around the hub.

We switched the front to the backs and the backs to the front without a change in the ossillation. I guess that I could have two hub ring/spacers off but am somewhat skeptical at this point.

I really didn't understand the pounds of weight for the road force balancer that was discussed but querried the D/T manager about it. He mentioned that he had thought of that but with the amount of weight off of optimum that we are at we should not feel an ossillation only from 52-55 MPH. Additionally only at that speed, and not repeated somewhere else in the operating range of the car without feeling the same ossillation is confusing.

The D/T manager has brought up the Mercedes issue mentioned elsewhere in this forum with these tires. He feels that the wheels and spacers are fine. He wants to try a different model of Michellin, the HMVX, a V rated 245/45/18 tire with softer sidewalls. He feels that the Z rated Pilot A/S is not a good match for the Audi allroad.

Gary @ Ronal was helpful as well. He didn't think that allignment was an issue as the vibe is only at that one speed. He questioned me on which lugs that I was using, and if the rings were seated properly on the wheel backs. The right lugs are being used and Ronal tapes the hubrings on the wheel from their facility. He also questioned me on tire pressure which I, in turn, questioned D/T. D/T said that the tires were slightly under Ronal/Michellin's recommendation of 38PSI but at 37-36 there is not enough difference to make the wheel shake as much as it is.

Gary 's recommendation was the same as D/T's ...that is to change tires...although he suggested a Pirelli P-Zero. He also suggested that the A-6/allroad 2.7T cars are very very sensitive to driveline vibe issues with larger tires.

Both said that the Mich A/S tire is too stiff for the car. I almost have to agree with my limited knowlege, as the OEM P-6's on there now are soft and ride/track very well (tracking straight for 3/4 of a mile at 80 MPH without any steering input and no vibe or ossillation on E-470 at any speed).

I also checked the Replica wheels at Atchtuning and about everyother wheel (OZ, Borbette, Fitapaldi, Moda, Millie M, etc, etc) that I could come up with and found that there are few that do not take a spacer for the allroad application...Hartman had a five spoke and Fondmetal had a similar wheel that take no spacer or hubcentric adapter. Other than those, Audi (Trademark) wheels are the only choices that I could find (at + 3x the price).

Thanks for the help you guys! Anything else comes to mind let me know. I am supposed to get the other Michellins by Monday. Both Ronal and Discount Tire have been very helpful and good to work with so far! I will update.