Update on Sonata warped rotors

A few months back I posted an issue with the brakes on 02 Sonata. Car
had 75,000 miles on it and dealer had turned rotors twice and replaced
them once. The rough braking had returned and Hyundai decided they
were not going to honor their warranty. A bad decision on their
part.

I bought expensive racing rotors and pads for around $275 which worked
well for a few thousand miles and then the problem returned. I also
purchased a runout guage and checked the new rotors and the hubs and
the max runout measured was .0015 inches, well within the spec of
..004.

After the problem returned, I measured the runout and it was still
within tolarance.

I then had the original Hyundai rotors turned and they measured .0055
inches of runout, out of spec according to the manual. However, the
problem is now gone but do not know for how long.

Someone sent me a link to an article that claimed the problem was
depositis on the drum which changed the friction around the drum.
Also, someone wrote that he had fixed this problem by a series of 10
hard stops.

I am beginning to believe you guys. Was not able to fix the problem
by 10 hard stops or by sanding the rotors by hand but turning the
rotors fixed it. I told the machinest to remove the minimum material
when turning the rotors.

Anybody have any ideas?

And, by the way, have never burned out a light bulb in this car in 6
years.