nix

I have a 2006 @ 39k miles and a shudder/grinding sound periodically occurs in the front end when turning from a dead stop. Car has to be driven for a while, no sound when its cold and no sounds or vibrations at speed or on wide turns. I stop and then and as I take a sharp left or right turn at low speed there is this grinding sound and shudder (car vibrates somewhat) and then it all goes away in a few seconds. Stopped at the delaer, but naturally I could not recreate the problem (the're going to check their bulletins). The sound is very simliar to that of tires hitting the speed strips on the shoulder the thruway. Coudl this be within the steering motor, bearings? Any thoughts out there as what this may be?

05TouringRX8

Well if you checked with dealer, this probably isn't it. But, could it be the rotors are warped and need machining and the problem gets worse when they get hot? When you stop in a straight line, do you feel vibration in the steering wheel or brake pedal?

nix

No vibration from a quick straight start or at stopping; all nice & even. I did spend some time in a large empty parking lot today and have become adept at forcing this shudder to occur! Car has to have been driven for a while. I stop completely; foot firmly on the brake for about 30 sec; release brake; start to turn and apply a little gas. Shudder starts, car vibrates (brakes not releasing???) but, as I pick up speed, it goes away. At least now I can replicate it at the dealer!. Also tried it in reverse and get a similar noise & feel. Back to the dealer next week and a drive with one of their techs.

05TouringRX8

Do you have the wheels turned when you do it in reverse? Hard to tell without hearing or feeling it but it does sort of sound like something is getting bound up or is staying bound up and not releasing, like the brake calipers.

YaXMaNGTO

Dude!

Soooo... imagine the pads inside the calipers for a moment. you apply the brakes and they clamp down on the rotors. They get hot... really hot. The rotors get hot. You do a stop and then sit there for 30 seconds with foot firmly on the brake. All the heat from the pads are CLAMPED TIGHTLY on one side of the rotor when the materials are hot and at their weakest state, deforming the rotor on one side. Then you decide to take off. Those ******* are gonna hop like bunny rabbits. Then, the rotor begins to cool and HOPEFULLY returns to some semblance of its original shape.

I had a buddy with a Mustang LX 5.0 back in college. That guy use to brake from 100 mph to a dead stop, and then sit there with his foot smashed down on the pedal at a light or whatever. He wondered why he warped 3 sets of rotors, and other Mustangs weren't having a problem.

Duh.

It's pretty simple. DON'T DO THAT. Even in my wife's SUV, if I have a stop from 60 mph, and I have to jump on the brakes pretty hard, I give myself a few feet before the intersection so that while I'm waiting at the light, I hold the brake pedal as LIGHT as possible, and I also allow it to roll forward a tiny bit each couple of seconds so that I'm not hot spotting the rotors. Guess what? My cars don't have problems with warped rotors.

luckygrrl

nix, it sounds like you have the same problem as me, only the noise I hear comes from the rear of the car. took mine to the dealership too, but they couldn't diagnose it. if you find out for sure what it is let me know please. p.s. i'm pretty sure it's not a problem with the brakes, in my case anyway.

kersh4w

iTrader: (3)

rofl yax. go get em!

nix

Appreciate all of the comments. I'm going to play around with the car this weekend and see if I can zero in on what issue may be, brakes, steering or something else. Car has to go to the dealer anyway to replace a sunvisor, so while I'm there, I'll recreate the issue for their tech and will post an update. As for noise from the rear, I've read other threads which discussed differential issues and the need to replace some due to early failure; you may want to check the archives for this.