hi guys,

i'm wondering what the heck is going on with my car. when i'm braking, i notice that my steering wheel vibrates. the harder i brake, the harder it vibrates. i don't know what the heck is wrong with it. do i have an air bubble in my brake lines? i have no idea. please help.

oh yeah, my brake feels kinda spongy tite when i press it.

 

Warp front rotor. Need to resurface the rotor and possibly change the brake pads also.

Chu...

 

yup, warpped rotors, get it fixed

 

thanks for the info guys.

my brakes were last inspected around 2 months ago at the dealer and they said the pads are about 90% new. but i do notice that the front rotors look scratched up but the rears are as smooth as a baby's a$$. so i'm thinking it might be just the front rotors?

 

most of the time warp rotors only appear on the front since they do more than 80% of the braking

 

GSquiksilver, it can be your balance. Tried getting your tires rebalance first. That happened to me before.

tommy

 

If the rotors are warped, then you should feel the vibration in the brake pedal as well. Let a mechanic do an inspection...

 

yup, i do feel it in the brake pedal as well. thanks for all the input guys. i'm gonna get it done today after work.

 

Sounds like warped rotors...I would NOT resurface them, but suggest that you replace them. Turning them will only do so much and with the removal or more material, they will warp even easier after...Resurfacing is not the solution for warped rotors

 

i have this same problem, i got my rotors replaced last year and have recently noticed the shaking again. i don't think i should have to have my rotors replaced again, hopefully it just needs the resurfacing or balancing.

 

Sounds most likely as rotor warp. Probably front only. I've had rotors resurfaced (not on my GS) with success. I found a shop where they would only take off as much as needed to make them smooth, usually not much.
Read a paper in the SAE (society of american engineers) magazine "Automotive Engineering" that said the warping problem is not from heat per se, but rather from the non-uniform cooling. That is, keeping the brakes on at a long light after a hard stop causes the rotor to not cool at all places at the same rate. They suggest getting off the brake or letting the car creep a little so no spot sits against the brake pads very long. Someone having recurring trouble with this might want to try this.

 

what do you all think, back in january i had my pads replaced and rotors resurfaced and now the problem has come back. i had the work done at the lexus dealer ship do you think i have a right to complain that this is already a problem after just 9 months of driving?

 

It is my understanding that work done at Lexus has a warranty

 

kuruption213 - Don't know how far you will get with Lexus, I think we all know it depends on your relationship with that dealer, but nine months might be a bit long to say it was some defect with the parts they provided. Back in the good old days when cars were just starting to get front disk brakes, the first set of rotors I ever trashed was on a race car by pulling in off the track and going through a puddle that was deeper than I thought. Cracked a couple of welds on the exhaust pipes, no big deal, and warped four rotors, a big deal. Cooling uniformity is a big deal and one of those things that may not have anything to do with the quality of the parts. In my case, those rotors were trash as they warped beyond where they could be cleaned up with machining. Having said that, the rotors on the GS don't seem to be anywhere near the problem as they were on the bimmers. Not sure the exact reasons other than that marvelous suspension is very sensitive to out of balance components but it seems like all I remember was going in for either out of balance wheels or warped rotors once a quarter.

 

finally got my rotors done!!!!! woohoo! so far so good. i have to try them out on the freeway tomorrow. crossing my fingers....