I have a 2005 tC with 117K miles. I recently did a tire rotation (front to back) and afterwards noticed that there was an odd feeling in the wheels. I first felt it through the pedals and if I lowered the window I could hear it.

The problem is that the front driver wheel seems to have an off center rotation. At least that is what it seems like. It feels like I am going over a crack in the road with every rotation, almost like a bulge that just drops the car every rotation.

I lifted the car and turned on the car to let the wheel spin while in gear. If you put your finger on the tread of the tire, you can feel the tire rise then lower with each pass. At first I was concerned it was a wheel/tire problem so I took off the wheel and checked the brake rotor and it does the exact same thing. I also put on the hub centric spare tire to make sure it was something from the hub assembly on and sure enough the same symptom arises.

So what are your guesses with this? Wheel bearing? Since it was lifted off the ground, it can't be the struts (DG spec coilovers). The car is lowered, but the fender is high enough to still show the whole tire.

I'll have to shake it some more later to see what kind of play there is. My scissor jack had enough of me and some dirt must have gotten into it because it doesn't want to spin much anymore (College, far away from home for normal floor jack).

Thank you in advance.

 

So I got a lift and some jack stands. Put the car into fifth gear and looked at both front wheels. They both have the jumping feeling. At the same spot on the tire. When I got under the car, I could tell the shafts look like they also are wiggling with the tires. It makes a weird noise only at higher speeds, not in the lower gears. Maybe I can upload a video of it soon. I yanked on the tires and they are completely solid. No play. So I am guessing it's not wheel bearings. Could off balance wheels cause this? They haven't been balanced in about 3 years so maybe it's time to go ahead and do that.

 

so you feel the bumps on the tread on the inside or outside? sounds like you have cupping in your tires. you can google it but i suggest you get an alignment and set the toe in the rear to zero to combat anymore cupping issues. cupping will cause a low humming noise while driving so if you aren't too annoyed then you're good to go but if you are annoyed by it....then you gotta get new tires.

 

I don't believe it is a tire issue at all. When you get under the car, the axles do not spin perfectly. It's off balanced. Kind of like the axle in this video, just not near as bad. Bad language warning. https://www.youtube.com/watch?v=xzI-VtLXVQM#t=89


I think it might be my cv axles. When I grab the axle and pull and push it, it is like I am rattling the bar back and forth. My driver side has some grease running down the shaft from the boot. So their is a leak and I think that is causing a vibration through both axles. My passenger side was leaking a loooong time ago, but I sealed it before it got bad. Looks like I may have to replace both or atleast the driver side and reboot the passenger side. Only problem is that the decently priced aftermarket axles aren't balanced.

Anyone know how and where to get/replace just the outer joint of the CV axle? Or will I just have to hope I pick up a decent aftermarket set?

 

Appears to be a tire/wheel problem. Switched the tires around and the feeling has gone away from the front. I can feel it in the back now. I think a band inside the tire might have snapped or something causing a stiff point. It always felt like I was running over something. When the wheel was on the front end and I was driving slow enough, you could see and feel the car rising in just one spot during the rotation. It wasn't a smooth transition as if the tire was just rotating at an off axis. So now I need to take it in and get the tires balanced and see what they say about the bad one. It sucks, but sure beats buying some aftermarket cv axles that might not work well.

 

Try getting the tires re-balanced.

 

Got the tires balanced. Most of them have the same problem as the problem tire that I discovered. They said it doesn't appear to be a bad belt in the tire, but more likely low tire pressure wear. I find it odd it affected just one area of the tire causing the bumping feeling. I also usually have my tire pressure at or higher than the factory recommended (32f/29r). They put 40 all around with the tire max rated at 50psi. The only time I think the tire pressure may have suffered was during this cold weather Indiana had this past winter. I didn't really ever check them besides just visual to see if they look flat. They are low profile so it can run low before looking flat. So at least the tires are balanced and hopefully they last longer. The one tire is still noticeable, but since it is in the back, it doesn't worry me much. I also have one bent rim. He said it was pretty bad, but I don't notice it so I'll just run with it. Must be all the heavy turning I do. I'm not a speeder, but I do love taking turns fast.

 

If your car had been sitting for an extended period of time, it can cause a flat spot that will result in vibration. This usually does go away on its own however.

 

40 is too high. But 32 rear and 35 front when cold has always worn tires evenly for me on this car.