by mikekey » Mon Nov 25, 2013 10:07 am
If what I recall from around here they're the same all by like a few mm. Looks like the bore difference is your indicator. My main guess is that the difference is performance related, the same reason we have aluminum calipers and the SS's had iron calipers. But getting legit numbers would be a nice thing to know. Since everything is currently just base on what we all read somewhere else without an actual technical source.
Auto Parts stores might have different stock numbers for the same part btw. So it's not always 100%.
I have found that some of the ebay sellers are just checking all the boxes and are in fact not selling SS rotors or maybe even EXT rotors. I saw a few where the same set said if fit Trailblazer and Trailblazer EXT, Trailblazer SS, like WTF? I just had this problem with the G8 where a seller had listed G8, G8 GXP but the GXP has 16 inch brembos and he infact sold me 14inch G8 rotors and I had to send them back. The seller just thought GXP was a trim option.
Once lifted 03 Trailblazer on 35's, gave it up to travel the USA with my family.