Drive Train vibration?

[cincyken]

I have a 2007 M35, a great car.
In the mornings when the car is cold, for the first mile, I have a subtle vibration that appears to be coming from the drive shaft. After driving for about a mile, it smoothes out and the vibration is gone.
I took it to a local mechanic, he suspected it was the tires (sounded reasonable). He balanced the tires and said I should replace the tires (because they had "cupped" wear). The next day, I drove the car and the vibration problem was back. I tried an experiment, I accelerated, and the vibration got worse, I de-accelerated and the vibration went away. If it was the tires, the vibration would not have gone way on de-acceleration. I took it back to him, he put it on the lift and showed me the driveshaft. He said all is tight and the support bearing is fine.
It sure sounds like the front universal joint to me.
Anyone encountered this problem before?

[Larz]

Seems to me your mechanic did an inspection of the driveshaft and joints and found no issues. If your wheels were warped, etc that would have been found upon balancing and he reported no issues there either. I am not sure your 'test' was reliable. There are troubles with tires that will usually increase and decrease with speed, turning, braking, etc.
I had a similar situation with a set of Michelins on my 2007 M. I noticed the tires were not behaving as they had been and the road noise was increasing. I felt increased road 'feel', a vibration in the steering wheel, and increased road noise, but no vibration that seemed to be coming from the driveshaft area. I would expect tire defects to produce vibrations that seem to come from the tires and steering wheel, not from under the center of the car. However, vibrations can migrate from one area to another and mislead us as to the location of the trouble. Since your tires are cupped, they need to be replaced for safety reasons anyway, so I would do that first and see if the vibration goes away.

[MY06M45S]

Seems to me your mechanic did an inspection of the driveshaft and joints and found no issues. If your wheels were warped, etc that would have been found upon balancing and he reported no issues there either. I am not sure your 'test' was reliable. There are troubles with tires that will usually increase and decrease with speed, turning, braking, etc.
I had a similar situation with a set of Michelins on my 2007 M. I noticed the tires were not behaving as they had been and the road noise was increasing. I felt increased road 'feel', a vibration in the steering wheel, and increased road noise, but no vibration that seemed to be coming from the driveshaft area. I would expect tire defects to produce vibrations that seem to come from the tires and steering wheel, not from under the center of the car. However, vibrations can migrate from one area to another and mislead us as to the location of the trouble. Since your tires are cupped, they need to be replaced for safety reasons anyway, so I would do that first and see if the vibration goes away.

I second that ^^^ if tires are in bad shape, they can cause a lot of weird issues. Maybe try rotating them, front to rear, rear to front and see if that changes anything.

[Six_Legs]

Rotating the tires is a good idea for sure.
My experience with bad U-joints is that there is more of a clunk than a vibration when you hit accelerator while driving. I'm guessing your mech checked for any play in the joints. You mentioned vibration goes away, that clunk would not.

As mentioned above, bad tires can make a car feel like it's falling apart and yours are cupped.
I would rotate and report back, curious to see what you find

[cincyken]

One question before I rotate the tires, what will happen with the tire pressure sensors, will they still be working correctly after the rotation?
Now, as a comment about the universal joint. In 1968, while driving my 1965 GTO on the Penn turnpike, I developed a vibration that appeared to be coming from the driveshaft. Like a dumb 21 year old, I thought increasing my speed would smooth it out. But instead the vibration got worse and tore the 4 speed away from the bell housing. Yes, in most cases, there is a clunk, but not always.

[Trendwho205]

This is so Ironic because I am having this same issue I have a 2007 with 62k miles on it and started having the slight vibration coming from my from my drive train I was told by the dealership and the tire shop that I had to warp wheels that's the reason why it was vibrating so I got the wheels balanced and rotated still the same issue I also ended up ordering new wheels because I thought I was having issues with him being warped but that was not the case even when I got my new wheels no prob relation was still present and even worse now just this morning when I was driving I hit my brakes to stop at a stop sign and touched the gas to go and the car would not move all of a sudden I heard this loud clunk so I'm taking it to the dealership tomorrow to see what's going on but I just find it so ironic that you're having the same issue my issue comes when I'm driving in 4th gear and when the RPM's are around 2100 rpm and 50 miles per hour I get the vibration it goes away if I accelerate past that it goes away but only in 4th gear that's when the vibration comes if I hold the car at 50 miles per hour and 4th gear vibration will stay the whole time I did a YouTube video about this issue with no luck on getting any answers if I find out anything I will be gladly post back in the form and let you know what's going on but I think we're having the same issue

[cincyken]

Had the tires rotated but there was absolutely no change.
What's next?

[jdjack68]

Replacing them if they are cupped. Nothing will fix a cupped tire short of replacement. Rotating your tires regularly prevents them from being cupped, it doesn't do anything for one that already is.

[MY06M45S]

Had the tires rotated but there was absolutely no change.
What's next?

If your mechanic checked out the drive shaft, axles, etc and has found nothing loose or wearing, I'd say replace the tires. Tires are one of the biggest contributors to cause vibrations and "weird" feelings/noises for cars. As long as everything else checked out ok, then you might have no other choice than to replace the tires. What has your mechanic recommend you do?

[MY06M45S]

Besides telling you to replace your tires, has the mechanic recommend you do anything else?

[cincyken]

his response was to replace the tires, but I am not convinced it is the tires. I have seen cupped tire treat over the years, and this cupping is very minor. I am still confused about why it only happens when the car is cold and only on acceleration, but never on coasting or deceleration.

[CPJ LB]

if your tires are showing as 'cupped', then it might be a good idea to take your car to another shop to inspect the suspension more closely....if you have high mileage on your car, it might be a sign of the shocks and other suspension parts (outer tie rods) that need to be replaced. once you get everything dialed in, then get an alignment

do you have the sport or non-sport M?? KYB makes shocks for our cars - which will save you some money compared to dealer prices....

[cincyken]

I took the car to a local Tire dealer who sells the Kumo tires that are on the car. He put the car on his lift and then made the following statement:" I would love to sell you new tires but the tires you have now still have a lot of good miles left on them and the "cupping" is so minor that it cannot possibly be what is causing the vibration".
I guess I am back to square one.

[bluedevil30]

Did your mechanic check your brake calipers? I had a similar issue and it turned out to be one siezed rear caliper.

[cincyken]

He said the brakes are fine.

[djc1020]

I just had the exact same problem on my 06 m35x i thought it was a driveshaft issue as well until i figured out my pass.rear caliper was seized