Thread: Rotor Size

Hey Guy's have not posted in a long time. Here is my problem I change out my font calipers and rotors, I purchased the new rotor and calipers from advanced auto parts. Of course I did not compare the old rotor size to the new one before I got rid of the old one's (I know my dumb dumb need gum gum) So after putting everything together it seem like the rotors are to small. I verified 2 difference time with Advanced auto the they are the correct parts, but I don't think they are. When you look at the rotors and where they hit the pads, it's only grabbing 1/2 or 3/4 of the pad not sitting further up in the caliper. Question is, are there 2 different rotor sizes for a 1998 grand prix SE 3.8 l ? The outside diameters on the ones advanced auto sold me are 276.8 is there a lager size out there? Thanks



UPDATE

Ok guy's after much research and looking at the RPO. 11" RPO code is JB9 (Lite Duty), which is all the auto parts store sell you. 12" RPO code is JA9 or JL9 (Heavy Duty). The 1998 Grand Prix SE with body style W was equipped with the 12" rotors, mystery solved. Thanks for all the input, for future reference I know now to look for the RPO code. Just as a FYI for this car the sticker is located on the inside of the truck lid.

276.8 mm?
Can you post pics of how the pads are sitting?

My books show OD of 10.94" (277.876mm), and only one size listed. Even if you had the wrong size, a few mm isn't going to cause the problem you are having. Is the caliper and bracket on all the way? What part # rotor did they sell you?

This is what it should look like:

You can upgrade to the big brake kit that Police Impalas had. This car might have had that option added.

Basically it allows you to use a bigger rotor, this was made possible with a different caliper bracket. These rotors fit the Olds Intrigues, Monte Carlos, Police Impalas, or I just ask for a 2002 Camaro SS front rotor.

Basically they are FBody rotors.

Originally Posted by rynoman03

You can upgrade to the big brake kit that Police Impalas had. This car might have had that option added.

Basically it allows you to use a bigger rotor, this was made possible with a different caliper bracket. These rotors fit the Olds Intrigues, Monte Carlos, Police Impalas, or I just ask for a 2002 Camaro SS front rotor.

Basically they are FBody rotors.

Who puts bigger brakes on a 98 SE?

Originally Posted by Slick2500

Who puts bigger brakes on a 98 SE?

Stupider things have happened. LOL

True. I've seen a fully modded l67 swapped one once.

Sent from A Galaxy Far Far Away

SE gets bigger brakes? GM. LOL

SE like GTP special edition, not low end 3.1 liter SE

The OP has a 98 SE, it's the base model with the anteater front bumper.

Sent from A Galaxy Far Far Away

Power windows and locks are standard on all Grand Prix from 97 up.
Does it have Bose too?

Sent from A Galaxy Far Far Away

Originally Posted by Slick2500

Who puts bigger brakes on a 98 SE?

My LeMons car is a 97 SE with GXP brake all around LOL!!!!