I have a 2003 A4 coupe with a vibration above 50mph. The gear shift & seats will shake, then stop..shake then stop. The vibration or rumble will increase with speed. If I put the car in neutral it's still there. I had the rear tires "road forced" (balanced) same shake in the car. The car has 4900 easy miles on it, I'm lost & fear takng it to the dealer...Anybody have any ideas or have a similiar problem?? You guys think driveline, like driveshafts ? rear ? HELP

Pat

 

What kind of vibration are you feeling.

If the vette is in neutral and you hit the gas, you state that you are getting a vibration. If that is the case, it could be either the torque tube or some internal engine problem.

Have you check the DTC for codes ? If so are there any showing ?

Have you checked to see that all of your motor mount, rear and drive line harware is properly torqued.

It appears from your description that something is out of balance. Did you check the harmonic balancer ?

 

The vibe is coming from the rear of the car. I have not checked for codes..The shake in the car comes in at or above 50mph for a couple seconds then dissapears..comes in the goes away. The frequency increases with speed, I've beenm told tires, & poss driveline components. Feedback from the forum first, then a trip to a "trusted" forum tuner is probably the nest step.

 

check the cv joints. You may have one going bad. If it is you should maybe see some grease slung around from the boot. Alo after you have drove it then feel the back side behind the rotors where the bearings wouls be to see if one side is hotter that the other. Just don't touch the rotors! They will be hot

 

Your vibration sounds like a classic wheel balance problem. The fact that it occurs with the car in nuetral eliminates the engine as a source. Although the drive train could still be a problem I doubt it. I had an imbalance problem on one of my track tires this week and it caused the shifter to shake like hell at certain speeds. Just because it feels like it is the rear does not mean it is. Check the balance on the front wheels also. Go for the more likely fix first before getting escoteric.
Bill

 

You might want to check your rotors too. Good luck

 

Sounds like 2 or more tires have either flat spots from sitting, are unbalanced or tires are just out of round. The 2 tires will be out of balance or whatever at different revolutions. As soon as you turn the car and make the outside wheel turn faster, they will make a slightly different harmonic frequency. Like it vibrates for 2 seconds long every 5 seconds. Then you go around a bend and it does it for 3 seconds every 8, etc.
Put the rear on jackstands or on a lift and do 60 with the T-A/H off and see if the car starts to shake. Or at Idle in gear you can see if the tire rotating slowly is out of round.
I had that problem with flat spots on a trailer that sat for 2 years.

 

I had a buddy that hit a curb... bent a rim... the steering wheel vibrated above 50... he replaced the rim... it got better, but was still there. It ended up being a pinched wheel bearing... Everyone kept saying wheel balance... they were balanced.. the front hub was bad.. it got replaced, and it is back to normal now... my .02

 

Over inflate the tires to 45psi and drive it again and see if it improves. The extra air will minimize the flat spots. A 3 year old car with 4500 miles is all but new. I'm sure you would have remembered curbing the car and even GM has better luck with wheel bearings than that. I'm also guessing that you still have the runflats on. The tread is thicker so flat spotting will last longer and be more pronounced. If you don't intend to drive it for aprolonged time, overinflate the tire to stop the flat spots from coming back. Typically you'll feel a "front end" shake through the steering wheel.

My last truck had the same shake and I was prepared to replace U-joints and other components but after looking at the dryrot on the tires I decided to replace them first. Problem fixed.

I wouldn't replace them just yet. Give them some air and time to re-shape.

 

This may sound crazy...but make sure (if you have directional tires) that they are mounted correctly and the arrows are pointing the right way. I have actually heard of this happening where the tire shops dont realize they are directional. This causes major vibrations, usually at 50 mph.

 

MY $.02 is pull the wheels off and look at the studs sticking out of the rotors. If there are round metal thin washers on any of them take them off. Remount the wheels and then take the car for a blast. They will throw the balance of a wheel off as well.

 

Thanks for the help ! I'm going to schedule the car for a 4 wheel road force balance next week. I will first crank the tire pressure up too see if it helps or not. This is more of an annoyance than a real "issue" at least I hope that's the case. I've only spun the wheels a couple of times on this thing...Maybe I need to CLEAN the rubber a little

Pat

 

Any chance you have changed rims?? Might have gottten one that was bent or out of true from factory.

 

Funny this got mentioned because I too was forced into a curb a few months back and cracked both rims on the passenger side of the vehicle. After replaciong both rims and the vehicle passing a complete visual inspection I was back on the road. Almost immediately (within a few days) car began to experience the EXACT SAME vibration you are describing above 35 mph. Car would vibrate in any gear (98 A4) including nuetral.

Took the car to several "Vette Shops" here in South Florida and even the dealer. Everyone explained it was a balancing issue or alignment issue or brake rotor issue or some other nonsense. Had the car aligned, balanced, the works. Vibration began to get progressively worse and I finally took the car to a local import shop (FyneTune Performance) who now does ALL my work. Mechanic drove it, then pulled it in and placed it on the lift. Took the right rear tire off, and disassembled the wheel bearing. You could see were it was pinched and there was even some slight accumulation of metal shavings. Dealer wanted over $400 for a new wheel bearing. The guys at the import shop advised me to go get a Timken wheel bearing from Autozone. Bearing cost me $130 with sensor. After installation I have had NO issues and the vibration has not returned. Please have your wheel bearings checked before wasting more money on balancing, alignments, etc.

 

Thanks to everyone who responded. The car has never been curbed & has the factory wheels in place. Bounty, I'm going to have the rear bearings looked at by the guys at FTP I think yet this fall. Long way to travel but maybe I'll do gears & convertor while I'm there.