Hello Forum,

Me and my brother are working on his 09 G37 Sedan with non-sport brakes. We are trying to replace the rotors because the car shakes real bad when applying the brakes. We were told by an Infiniti tech after inspecting the brakes that this was being caused by thin rotors.

We purchased new rotors from O'Reilly's and they appeared to be the correct ones. However, after placing the rotor on the hub and remounting the caliper mounting bracket, the rotor does not spin freely. After forcing it to turn we see that the rotor is rubbing mainly on the outer perimeter but also on the outside surface.

So at this point we compare the new to the old rotor and although it is very close, it appears that the new rotor is a two or three mm larger in diameter as well as at least 1/4in thicker.

My question at this point is if there is anything that you guys can think of that I can do to the car to accommodate the new rotor? Perhaps something that I may have overlooked. Or is the new rotor simply not the correct size?

For what it's worth, we reinstalled the old rotor and it worked perfectly.

 

The 09 non sport sedans have 320mm front rotors that are 28mm thick, rear rotors are 308mm and 16mm thick., the 09 coupes (non-sport) have 330mm front 32mm thick & rear rotors are 330mm 16mm thick, Sounds like you got the non sport coupe rotors by mistake

 

Wow, that makes perfect sense.

It sucks that I got the wrong ones but at least you have pointed me in the right direction. It never even occurred to me that they may coupe rotors. Thanks for the info and help. I will post an update once I get a chance to return to O'Reilly's.

 

So they were indeed the incorrect size (coupe rotors). I exchanged them for the correct ones and they are working great. Once again thanks for the help.

 

Glad it worked out and also that you didn't try to "make them work", lol.