Brakes shudder slightly – you feel it in the break pedal and not so much in the steering wheel
when dropping through the 50 to 40 mph speed. This is not as pronounced when brakes
warm – more pronounced when they are hot.
Dealer did an on-car rotor de-glaze, turn, and said they removed a slight warp.
Unfortunately, nothing has changed. The dealer said everything ok now … I found out they never tested the car.
Other than that,
The car doesn’t seem to pull to either side.
The car stops straight.
The car stops strong.
Any ideas of what may be happening? Is this symptomatic of
G35 Sedan or just a general brake issue?
Thanks for any input/ideas.

 

take it back as those rotors are warped. hopefully you are under 36K on the mileage

 

More research -
Brake Rotor Pulsation: Causes. [Comments from Wagner Brake div. Of Cooper Industries:] Brake rotor thickness variation causes brake vibration due to changes in the braking force as thick and thin portions of the rotor pass between the pads. Eric Smith, Senior Instructor for Wagner Brake at the Moog World Training Center in St. Louis, says technicians sometimes pin the blame on a defective rotor, but often it's due to excessive system run-out, which has not been checked by the technician.
Smith says the run-out will cause the rotor to wear itself out of parallel, and is why turning or replacing the rotor won't solve the problem. System run-out can be caused by poor mating of flanges between the hub and rotor when assembled as a unit ( by excessive rust, preventing a clean fit of the rotor on the flange), excessive run-out and even improper torqueing of the wheel bolts. Once the rotor heats up during operation, if one lug is a little less tight that the others, the rotor will expand at that point and cause run-out, says Smith. Compounding this is the fact that the brake might only have run-out when the rotor is hot. When the customer takes the car back to the shop, it's cooled when checked by the technician and by that time the run-out disappears. If not corrected, though, it will eventually have a permanent run-out, and be worn out of parallel.
Make sure rotor run-out is below specifications before reinstallation; also make sure the hub is clean and rust free before installing the rotor. System run-out should be checked after installing the rotor (new or turned). If run-out is above spec, the solution may be as easy as re-indexing the rotor one stud at a time, until run-out is within spec. It may also be necessary to replace the hub assembly.

 

I am having the same issue on my 05 sedan. Somehow I can't stay away from my vibration issues, first the tires which is still present and now the brakes...

 

Man this thread is old, but I get flamed for creating new ones. Anyway, I have an 04 sedan I replaced the front rotors and pads a few months ago and I thought that the terrible brake shudder I got would go away. It did not. It's been with me all this time. Assuming I torqued the lug nuts equally and there was no rust, what could I have done to cause this? Brakes never come from the store with runout, do they? I got safety stops or something or other from NAPA. Took me forever to realize that the brakes for the auto coupes were the same for the sedans. It was either that NAPA didn't have rotors listed for the sedan or there was some other issue with me finding what I need back when I got these. I don't know if I feel like taking them off again just yet, but if somebody that knows or that has experienced this can tell me what the deal is, I'd appreciate it. Thanks!

 

I had the rotors resurfaced and that fixed my problem 06 G35 sedan the yearly g's have rotors problems that might be it.

 

Thanks, dude. Do you or anyone else know how much this on-the-car resurfacing costs? I would think that it would be far more expensive than taking them off and doing them. I'm just wondering if this would be necessary for me to get, since I installed brand stinkin' new rotors and got the same vibration from the start.

I think I may just take them off and take them to Pep Boys and get them machined and see what happens. Although doing that is basically like me saying that they were messed up from the store. Which I have a hard time believing.

Correction to my previous post, though. I think these are the rotors I have. Perhaps I should have gotten these.

If they're shuddering because their cheap, I think I'll just live with the shudder until they wear out. Or I suppose I can just keep getting them machined now and then when the vibration inevitably returns until they wear out.

Oh yeah, I got the low dust ceramic pads. Maybe not fully ceramic, I can't remember, though. You think they're too hard and warp the rotors?

 

maybe u should've gone with OEM rotors, i had break squealing until I got OEM pads