I'm trying to figure out what the size for my rear rotors is. 2001 GMC Sierra SL 4.8 liter V8 and 3.73 gears. My rear rotors are warped so I was looking into some stock replacements. The two sizes are 325mm and 330mm; which comes out to 12.795" and 13". Which one do I have or how can I figure it out without taking the rotor off and measuring? I'm being a little lazy since I don't want to take off the rotors except once

Thanks

 

Pipe me out your VIN# and I'll get you the Part # you need in like 2 minutes

 

Cool; just sent ya a PM. Any more ideas? I know somebody has changed their rear rotors......