I need some help from all of you. As you can see on this previous thread:
https://g35driver.com/forums/showthr...6&page=2&pp=15

I have having vibration problems with my car. Dealer is saying that all tires and wheels are to spec and they are not feeling the vibration. Mind you I drove the car with their mechanic and he indeed felt the vibration. Now the service manager is saying it is road feel. I know what road feel is, I have had previous high performance cars and I know this is no road feel. Please check your cars as you drive around 45-50 mph, 60-65mph and 70-78mph and tell me if any vibration is felt on the steering wheel, if the passenger seat vibrates, very noticable around 70mph, it just shakes none stop. I have had three loaners from this dealer with very high mileage and not one vibrates. Any help or advise appreciated. Thanks

 

My car does not vibrate as you mention at any speed.

Questions:

1 - is it constant, or does it come and go during the speed windows you list?

2 - is it consistent, or can you drive the car at times and have no vibration at all?

3- have they done anything to try to fix it?

In the past I've seen many things cause this problem.

1 - Warped rotor - not likely on a new car but you never know.
2 - Wheel out of balance. sometimes a spin balancer won't catch the problem. You may have to use a service that balances the wheel on the car to get it true.
3 - Bent rim.

More data please. I would say you have a problem and it isn't 'road feel.' I had a similar set of symptoms on my Maxima and it ended up being a balancing/warped rotor issue.

 

No vibration here either. Car tracks smooth as silk.

 

No vibrations or rattles so far.

 

Here are three things you need to have the dealer check:
1) tires, one little gouge on a tire will give you virbations
2) balancing the tires
3) alignment on all 4 wheels

your problem lies in one of the three.... hope this helps.

 

Answers to all the questions posted:
1. Problem is consistent at these speeds
2. First time in the dealer, they replaced all four tires for brand new ones. THey have measured the tires and wheels and all are within specs from manufactor.
3. They have rebalanced and realinged the car
4. They have tried everything supposedly, not sure about the balancing while still mounted on the car, will check tomorrow

I did call the GM of the dealer today to get him involved. What ticks me off is that the mechanic felt it with me and now they are trying to change the story around. Thanks for all the help and info...

 

Could be a warped rotor. I know it's unlikely but possible.

When they replaced your tires, did they replace your rims?

Get them to swap a set of tires off their DEMO onto your car for a test run. It won't cost them anything and will eliminate the bent rim possibility.

 

I would assume the dealer has done nothing (in other words. all the things you said he did, he never did). Try the following:

1. Buy a good 1/2" torque wrench from Sears with a short extension and a metric socket that matches your lug nuts.
2. Take each tire off and inspect for obvious road damage (do not use torque wrench to loosen lug nuts!).
3. Hopefully nothing wrong. Then put tires back on and properly torque your lug nuts (gradually bring each lug nut up to torque value going around in a star pattern).
4. Hand spin each wheel. Listen to wheel. You'll be able to tell if you have a warped rotor as the brake pads slightly rub the rotor normally and a warped rotor will sound a lot different than the other wheels.

Go for test drive to see if problem is solved.

 

EX MGB, I agree with you. I am sure nothing has been done by the dealer since it is normal BS from them. I will attempt what you said once I get the car back.

GeeWilkers, I was thinking about that but have not suggested it until I hear back since I just spoke to the GM. I was also going to suggest for them to let me drive other G35 sedan same as mine to see what happens. Thanks again

 

05 X here and there is no vibration at any speed. Perhaps it is a drivetrain vibration such as a drive shaft, etc? Also, did you try another dealer?

 

I have logged about 8000 miles on an 05 and no vibration problems at all.. I think I notice some flat spotting on the ELs when cold, but nothing at any speed all the way up to 110..

 

It is an absolute requirement of car ownership to own a good torque wrench and personally torque your wheels after anyone has touched it. I think the dealer is jerking you around hoping to pull some bogus warranty repair claim.

Always, always check the obvious, easy to rectify stuff first yourself! I speak from long, painful experience.

 

no vibration here either. I also think the dealer is trying to shift blame!

 

No vibrations with mine either. My car is running tight and smooth at low speeds and high speeds on the highway.

I had it stock for a week, before I lowered it with Eibach Pro Kit and put 20's on. Even after the mods the car felt even smoother than stock.

If your dealer claims they checked the balance and so on, if they did not ROAD FORCE BALANCE any of them, chances are they used a cheap machine that is completely useless in my opinion.

I would find a local shop that has the HUNTER WHEEL BALANCER and have them take a look at them. They will check the balance, rim runout, and roadforce on the tires, which may be causing the vibrations.

You'd be surprised how badly balanced your wheels might be right now if the dealer did not use this machine.

You did not mention if your running stock wheels or not. If you're not, make sure you have a hubcentric ring on all four wheels and that they fit properly. I had a ring on my old car that was 1mm bigger and caused my car to vibrate enough to notice it.

If that doesn't work, there is definitely a mecahnical problem such as the drive shaft or rear end. Hopefully not, but keep that in mind.

Good luck.

 

Hmmm. I don't think driving another G will tell you anything you don't already know. The guys here have responded and said theirs are good to go, I can tell you mine is good to go - there is something needing repair on your G. if you drive a demo and it rides smooth (100:1 it will) then you will be back to square one.

I suggested the 4-out tire swap because I've seen guys with bent wheels go around and around with their dealers - balancing, rotating, rebalancing, arguing, replacing tires, etc. The above seemed like a good way to eliminate balancing, warpage, and bent rim issues all at once. If you put 4 new do-nuts on your G and she rolls smooth you will know there is a problem with your wheels/tires. If it doesn't, you know the wheels/tires aren't the problem and you can move on to brakes/suspension.

Keep us posted on how things go and don't let the maintenance weenies tell you there is nothing wrong with your car. If you're getting a vibe like you describe then something isn't right and they should work with you to get it resolved.