When my car 05 G35x (560 miles so far) sits over night or the 12 hours I am at work, I get a vibration in the steering wheel that lasts for maybe 3-5 miles, then it is fine. Until it sits 12+ hours again.

I think it is a flat spot on one of the tires.

When I picked up the car, they had the tires at 47psi. I called the service department who advised they do this to avoid flat spotting when the cars sit on the lot and they must have forgotten to let the extra air out during PDI.

I have since set them to 30psi per the door sticker.

Any ideas?

I figure no sense in taking it to the dealer as it is guaranteed I will get a "unable to duplicate customer concern"

 

What brand of tires are on your car.
Are they bridgestone el42s or goodyears?

 

I get the same thing ....dissapated after increasing my psi to 35/36

 

What you describe is eaxactly related to a flat spot on the front tires. Can you feel the vibration in the seat as well as the steering wheel? If so, then you have flat spots on front and rear tires. I had the same problem on another vehicle and the only way I got rid of it was to change out all four tires. The issue was also worse in the winter when the temperatures were cold. I'd take the car to a authorized tire manufacturer for replacement since the tires are warrantied seperately from the rest of the vehicle.

 

The EL42s on the car are crap. I would not allow them to put another set of those on my car. They have documented problems and unless they are willing to swap them all out for a different tire, the best thing you can do is live with it and replace the set at some point.

 

Yup, Bridgestone EL42

awful tires, in 560 miles I have already started showing wear on the shoulders, these things roll over like a buick in turns.

 

Not the greatest tires, but increase the pressure slightly to help the issue.
Flat spots on tires is common.
C.

 

I took the psi from 30 to 35 and the vibration is almost gone after sitting. Good.

Now I can feel the road surface alot more. Not so good.

 

So, last night I went out and drove around like a real a$$ taking turns like a lunatic and today the vibration is almost gone.

These tires are actually not that bad, I took a increasing radius turn at a stupid speed and they hung on..no VDC intervention even.

Wife said she was going to vomit...always a good sign!

 

Guys, this is the same problem the Acura TL has been plagued with!! Acura now puts Michelins on the cars to fix the problem. Same EL42 that is on the TL is on the G35. Bridgestone obviously has a problem with that tire.

 

Do you have any links documenting the issue?

 

If anyone needs a spare EL42, my kid swings from one in the tree in the back yard with the one I asked for when I got rid of those pieces of crap. I think it still has a good 25K miles left on it.

 

www.acura-tl.com Do a search or even browse. You can find a ton of problems about vibrations.