Originally Posted by PNWjeeper

But no one knows what the minimum thickness is for a stock rotor before it can no longer be considered safe to turn?

Originally Posted by PNWjeeper

But no one knows what the minimum thickness is for a stock rotor before it can no longer be considered safe to turn?

Originally Posted by Radi

Steel is not steel is not steel. The chemistry, including additional boron to make crappy stock appear a little better and high levels of impurities that lead to brittleness and cracking can vary wildly.

I agree with you on recycling but it has to be done right, without obfuscating test results as the Chinese steel industry loves to do. What you order is not often what you end up getting. Questionable is OK for Tonka trucks but not brake parts.

Originally Posted by salad

1999 FSM says minimum thickness is 22.7 mm, max variation 0.013 mm, max runout 0.12mm (no idea what that is)

Originally Posted by PNWjeeper

Thank you salad I'm guessing max variation is the difference in thickness from one rotor compared to the other.

Originally Posted by Nick-B

The problem with unknown metals in a brake rotor has nothing to do with rust but rather the friction characteristic of the particular grade of steel used. Some grades will work well against the friction of a brake pad and some not so good. Worse, some will have tendency to work harden and resist pad friction and reduce stopping power.
That said, I've had cheap Chinese rotors that were awful an some that were excellent. That is the main problem - little or no quality control in many of those products.

Originally Posted by salad

Maybe - I would consider that to be the evenness of the rotor itself. Anymore and the rotor wouldn't be even thickness and will cause poor braking as the pads basically hop or bounce across the surface.