I own an '06 G35X and I have approx 95K miles on it. Its slightly lowered on sedan spec'd H&R's and coupe 19" rays. I was driving with this spring / wheel setup for about 60K miles without any issues. Recently I just replaced my tires with brand new Continental Extreme DWS all seasons, and did full re-balance and wheel alignment. Drove on them already for about 4K miles and the ride was nice and smooth until now.

I drive about 500miles a week on my work commute and recently when I cruise at 60mph, halfway into my commute the whole car starts to vibrate very aggressively as if I hit a pot hole and my wheels are out of balance or my tires are completely out of round. The whole car shakes and you can feel the frequency of vibration increase as I increase the speed of my car. The weird part is that it started happening all of a sudden on a smooth pavement, continued to vibrate for about 10mins and then the vibration goes away and my ride is smooth again. This process repeats probably once or twice during my commute to work. What do you guys think this is? If it was the counterbalance weight getting unglued from my wheel, the vibration would not stop, and the root cause would clearly be the wheels. Any root cause relating to wheel/tire balance, vibration would not stop at any speed. In my case, vibration sperratically starts happening, then goes away and I retain the smooth ride of my car.

Sorry for long writeup, any suggestions or ideas as to what this could be?
Thanks.

UPDATE: Well the problem came back with a vengance and this time the vibration kept recurring a lot more frequently and more prominently. I did notice that the car becomes very sluggish during the perioud of vibration. Yesterday I was pulling into my parking garage and while being in reverse and windows down, I kept hearing a loud scraping noise only when depressing the brake pedal, the car was also moving a lot slower in gear, I had to give it extra gas to just get it going. The noise was coming directly from rear driver's side brake caliper. From this point on the problem was obvious: one of my rear calipers locked up. I guess while driving the caliper kept engaging and disengaging the rotor causing the vibration. From constant pad to rotor engagement, the rotor warped, causing a more severe vibration while the car was moving. Could also be a faulty brake line for that wheel as well. The car is at my mechanic and the whole caliper assembly is being replaced and the rotor resurfaced. I really hope this is the culprit.

 

i have the same thing happening to my 04. i put air into my tires and it seem ok but i know thats not the solution to this problem. i would like to know the soultion if someone knows this.

 

Mine does this too once in a while. I have the same tires...Conti extremecontact DWS...but it did it on the previous goodyears.

Car will have a light vibration when i get on the highway that goes away after a few mins. Seems like it happened more on cold tires and after they warmed up a bit it would go away. It's never been too bad though..usually just a mild annoyance than anything.

 

This is strange. I was just contemplating posting about my experience, which just so happens to be the exact same that you described. Mine is an 05 X with about 68k and about 4k on the continental dws tires. Stock size wheels and tires. I thought that it could be a bad cv shaft some where but it was not a constant problem more of an intermittent problem like you described.

The good thing is that it usually settles down after a few minutes. It does seem to be a little worse when it is colder outside. All this leads me to believe that it is definitely a tire issue. Whether it is the tires itself or perhaps the tires being slightly out of balance.

If anyone comes up with a solution let me know. I have considered getting the tires rotates and balanced to see if it would make difference.

I thought for sure my situation was too specific to have had anyone else experience the same thing with the same tires. Got to love the internet.

 

Gonna have mine high speed balanced in the spring. Pothole season will be here soon and I don't want to waste a good wheel balance now.

 

maybe is the tires looks like 3 of you guys have the same tires and are having the same issue..i have a 2005 X with 79k miles with no issues at all..on my 3rd set of tires..right now i have the goodyear eagle GTs

 

Mine did the same thing with the oem Goodyear eagle rs-a

 

drove additional 150 miles, the vibration hasn't occurred , regardless I'll be taking my car to the dealer (for pass. airbag sensor recall) on Monday and I'll mention this issue. I'll let you guys know what profound wisdom they'll bestow upon me.

 

Try retorqueing your lugnuts. I've had similar symptums when a wheel loosened up on my Max. Also had a knocking sound. It would come and go depending on wether I was going straight or on a curve at highway speed.