HELP! Shaking...

[goldensandm45]

I've recently concluded that I would need to live with this mysterious shaking in coming from my steering wheel. I've taken the vehicle to numerous places to have it assessed and NOBODY has been able to diagnose the problem. Here is a list of areas that have already out have been ruled out.

1) The entire car has been balanced and shaking still occurs2) The rims are NOT bent as I've replaced them

The weirdest thing is that it only occurs during speed at around 60 mph as above has a rattling sound and DO NOT ALWAYS HAPPEN. Depending on the change in road surface it is intermittent.

I'm assuming that it has to be a suspension part that has gone bad. Any suggestions or has this M45 been badly possessed?

[Q45tech]

The frequency in Hertz of any vibration depends on the loaded circumference of tire and speed of rotation.If the vibration changes amplitude as a tire warms up it proves the tire is the cause.

Nissan has a radial force specification.....max number of upward thrust pounds per tire. What does each tire wheel measure on a Hunter 9700 machine? Important to measure tires at cold and hot temperatures as the force will change. Important that the 9700 exterts at least 600 pounds to squish the tire down to simulate loaded operation...................ideally the machine should perfectly mach the weight force on each specific wheel.

But this requires too much HP [frictional drag created] and many 9700 operators use less because they haven't updated machine.

Nissan requires dealerships to have Hunter 9700 now and hopefully someone is trained to use it properly without taking short cuts!!!!!!!!!

[szh]

What tires are you using? How many miles on them?

Z

[goldensandm45]

Well, they are Michelins,245/4518 Sports A/S and I've had them for about 10k miles. But the shaking occurred well before they were replaced. I know going to the dealer is my best bet but don't want to be a sucker by having them charge an arm and a leg. Is there any possible suspension components causing this shaking?

[peter_rabbit]

Have you recently had your rotors replaced or turned..? When i 1st purchased my M in August it had a mild vibration. The dealer turned the rotors and the vibration went away. Not saying this is true in your case but hey you never know

[szh]

You may well have a bad tire (or two) too. This is extremely unusual for Michelin tires, but it has been known to happen ... try contacting them and see if they will refer you to somebody who can check the tires out.

What is the date code on the tires, by the way? This is usually a four digit number near the DOT symbol.

Z

[goldensandm45]

So rotors can be the problem? I'm assuming nothing in the suspension can becausing this--like a strut or something that is loose or went bad or am I wrong? I'm sure it's not the tyres because I've had them rotated and the shaking still persists? What to do next?

I was debating on getting a higher performance from my existing 245/45 18 (Michelin sport to A/S) and upgrading to Michelin PS2 (<---I've heard these are far better) but is it overdoing it? Will I feel a difference?

[akliquid]

I had same the same problem. The warped rotors are very common, and it causes the steering wheel to shake sometimes quite vigorously at higher speeds. I replaced my rotors with aftermarket ones with Infniti pads, and have not had problem since. Whether you go with stock or aftermarket is your own preference, and resurfacing will help but not a permanent solution.In my case, shaking occurred mostly under braking. I did feel shaking other times, but it was most when brake was applied.

[maxnix]

Next time you change tires, have them spin up each wheel by itself to see if they meet OEM specification. Many inexpensive aftermarket ones do not, expecially after some miles.

[szh]

I had same the same problem. The warped rotors are very common, and it causes the steering wheel to shake sometimes quite vigorously at higher speeds. I replaced my rotors with aftermarket ones with Infniti pads, and have not had problem since. Whether you go with stock or aftermarket is your own preference, and resurfacing will help but not a permanent solution.In my case, shaking occurred mostly under braking. I did feel shaking other times, but it was most when brake was applied.

In many cases (not all), vibration during braking is not due so much as to warped rotors as improper seating of the pads after the install. If not done right, the pad material comes off in "clumps" on the rotors rather than a smooth coat, and then you get strange vibrations and the "warped rotor effect".

Definitely get a good brake technician to check things out. I usually ask for a specific person (I forget his name now, of course) at the dealer I go to, because I know he is competent and does a great job of getting the brakes to perform well after pads are replaced.

Z

[xerexabante]

Are your wheels torqed correctly?