: Casting voids in rear disc brake rotors

04-27-08, 03:27 PM
Please see my other post titled "pitted disc rotors". This title was a mistake as these are not pits just in the surface of the rotors. They appear to be casting voids. How large/bad the internal voids are that can't be seen yet are unknown.

The title "pitting" understates the discovery and tends to minimize the importance of addressing the issue. Pitting makes it seems like a problem with just the surface rather than voids throughout the entire casting which could result with a catastrophic failure of the entire rotor!

Pictures have been included.

04-28-08, 08:34 AM
Our companies worked with a lot od casting, and some are better than other, from your pixs it was tough to tell if they were surface pits or inclusions in the castings, if the pits are thru the castings you may get new rotors from GM, I would show them to the service manager. :)