My car suddenly developed a shuddering vibration over about 30km/h (18mph). It seemed to happen after I launched the car from a stop (yeah, I know… not a great idea). If you push in the clutch and turn the car off and coast, it is still there.
I just had my tires changed and balanced, so I checked all the wheels to make sure none were loose. They all seemed good.
Any ideas?
Car is a 2000 A6 4.2 w/ 6spd swap and engine upgrades
What flywheel have you got?
Fidanza Aluminum
I am wondering if I bent one of the axles
Dont tell me Im going to have to send my second Audi to the Twins. They only have three bays! Argh!!!
does the shudder frequency vary with engine speed or wheel speed? to test get in 2nd and accelerate from 2k rpm to say 5k rpm, then shift into 3rd and 4th while maintaining the same speed.
I tore the front motor mount on my A6 launching, so it could be something tame like that. I also tore the oil pressure sender wires loose launching one time, that one was scary at first.
Given you just swapped wheels, might as well check the wheels again, taking them right off…very possible something can be off esp if you’re using spacers (if).
Front driveshaft trouble was common with allroads of the same generation, cv joints (both inner and outer) getting frozen at times but looked ok when you’d check. Can get very frustrating…
I would say wheel speed, since I can turn the entire car off, coast, and the shuddering is still there.
Good idea on the wheels. yes, I am using spacers. I had another issue one time that felt exactly the same. It turned out the hubcentric ring lip on the spacer had cracked right off. So, the wheel was no longer hubcentric, and wobbled. Ill have to check that out.
So, considering that the problem still exists when the car is off and gliding in neutral, does that rule out the axles or the driveshaft?
Vibration seems to get worse the faster you go.
Motor mounts are 3 months new 034 units.
Driveshafts still spinning, yes. Frozen cv joints lead to a wobbling driveshaft, basically, but it’s more of a long shot in your case…I just know most with allroads experienced this issue.
I hope it is just a spacer or wheel issue. That would be easy to sort out. Ill check it out
Well, whoever guessed the problem was due to the wheels spacers, you WIN the big prize.
The prize is a pair 10mm hubcentric wheel spacers with their hubcentric lips broken off.
On a positive note, this was about the least costly of all things that could have been causing the issue. So, I am happy 
Mental note, do not use 10mm hubcentric spacers on an Audi. 8mm non-hubcentric or 12mm hubcentric only.
Nice one. Make those into something cool. Maybe a frisbee for bad kids.
LOL.
Lol, keep them, i don’t want them… I’m running 15mm H&R hubcentric spacers on the allroad, but they are straight, yet I do have a little driveshaft wobble, nothing major though. It’s all apart now anyway so thanks for reminding me to look at this…