2001 XG300 - Rotors

pulsation when applying the brakes. It did correct the problem both times. It was not covered under the warranty. Has anyone had this problem? Is this a problem with the XG300?

Hi Johnam - I suspect it's not a problem with the XG300 itself as much as it is a problem with the rotor/pad combination Hyundai selected for the car. This is not so uncommon a problem with long life pads on any car. You might want to try switching to a "lesser" grade of pad next time. IMHO, it's better to treat the pad as the greater sacrificial element of the brake system, than the rotor. I change out both when I do a brake job so it's not a matter of getting twice the life out of my rotors compared to my pads, but softer (easier wearing) pads will greatly reduce rotor warping, thus those nasty pulsing sensations.

What was the explanation as to why the resurfacing was not covered by warranty?

when applying the brakes. It did correct the problem both times. It was not covered under the warranty. Has anyone had this problem? Is this a problem with the XG300?

Did whomever surfaced your rotors give you a break-in procedure? If they didn't, then it is very easy to "imprint" the fresh surface all over again. Same when you replace the pads.

I used to belive in the warped rotor theory, but I've read several articles in the last couple of years that suggest a different theory and I think it makes a lot more sense. The theory essentially is that the rotors seldom really warp (and you can measure this with a dial indicator to be sure). The problem is differential friction around the circumference of the rotor caused by several things such as uneven buildup of pad residue on the rotor, rust spots from parking after a rain storm, or coming to a stop with hot pads and rotors and then holding hard on the brakes.

Matt