I have an 05 sedan 5AT w/ 39k miles with two problems that I hope you can help me with.

1) Rotors - I have had a pulsating problem with my brakes for the last 15k miles. I have had the rotors (all 4 corners) turned twice (the last time being about 1k miles ago). The problem is already back. I have to assume that the rotors need to be replaced, so what do you recommend as far as aftermarket rotors, or should I stick with stock (I don't want to change the calipers) ? Also, if I change the rotors, what can I do to prevent the problem from happening again ? Btw, I do not abuse the brakes at all. I've heard about tightening the wheels by hand, etc., but are there other things I can do to prevent the problem from coming back ?

2) Tires / Vibrations - I replaced my stock tires with Kuhmo KHs recently and I now have a vibration in the wheel when I am cruising between 70-75 mph. I had the tires balanced at the dealer and still have the vibration. The place where I bought the tires doesn't seem to be able to notice the vibration (they, of course, don't drive it everyday). Is there a certain type of balancing machine that would be able to detect it ? Could one of the tires be "bad", and if so, how would I find out ?

Thanks for your help.

 

Rotors warp. If they get extremely hot and you go through a water puddle, that'll warp them. Pretty much extreme changes in temperature will contribute. A trip DOWN pikes peak can do it to some rotors. At some point, most rotors have to be replaced. But 40K is a bit early. If they've been turned once, you may not have enough thickness to turn them again. Most any brake shop or machine shop should be able to tell you the thickness and if they are out of true before you just go buy new ones. If they were turned beyond tolerences, they will warp much quicker if not crack.

It's not at all unusual for new tires to have a broken belt or some other imperfection that makes balancing them difficult. There is a type of tire balancer called road force tire balance. They apply a force on the tire when they are balanced. I've used Discount Tire for my tire needs for many years. They do good work, but I don't hesitate to take my car(s) back the next day if there is a balance issue. They don't even drive the car. They pull the tires and balance them again. It usually is resolved with just the one trip.

 

http://www.stoptech.com/tech_info/wp...rakedisk.shtml