2 different size rotors

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Hi all,

Going to be working on a friends car in a couple weeks, putting all new brakes on.

2007 Jeep Compass
2.4L
87D101902 (last 8 of VIN)

RockAuto is listing two different size rotors for the rear, 262mm and 302mm and I have no idea as to which to order. Even on Jeep's actual part site it lists both for the VIN.
 
262mm is about 10.25 inches
302mm is almost 12 inches, about 11.9 roughly

Hopefully you or your friend have a calibrated eyeball. Otherwise, you must pull the wheel and measure.
 
1.5" difference is big enough to measure without removing the wheel, just need to hold a tape measure up to the face of the wheel and look between the spokes.
 
Originally Posted By: Throt
262mm and 302mm and I have no idea as to which to order.


Simple. Just measure what is currently on there.
 
The different rotor sizes are almost certainly tied to the option and/or trim level of the vehicle. For whatever reason, the catalogs you are looking at aren't discerning the model differences. The smaller rotor will have been used on the base model's wheel and tire diameter (perhaps 15"), while the larger rotor will have been used on upscale models that came from the factory with larger wheels and tires (say, 16, or 17").

I suppose there might be an exception somewhere, but in my experience a 15" wheel can only accommodate a 11" rotor. Maybe 11.25", that kind of thing, but not 12".

Especially since you are looking at a rear wheel fitment, where braking torque is always less than that required for the front axle, I would think you should be able to figure out what to use based on what size wheels are fitted to the vehicle, assuming they are not aftermarket units. Chances are there is a larger front rotor on the front axle than the rear, especially likely with the model with the 12" rear fitment, which is a premium application. The door sticker or manual may also help figure it out.

Also, I would suggest going to TireRack dotcom and see what they recommend. They are extremely accurate in my experience with regard to OEM fitment data, and they definitely do discern the OEM fitment based on option or trim level.
 
Originally Posted By: Johnny2Bad
I suppose there might be an exception somewhere, but in my experience a 15" wheel can only accommodate a 11" rotor. Maybe 11.25", that kind of thing, but not 12".


I think this is accurate. The first-gen Ridgeline has 13.1" rear rotors, and a 17" wheel is as small as will fit. You can't fit a 16" wheel to a Ridgeline as it won't clear the rear rotors (the fronts are only 12.6"!). 16s will clear a 12" rotor, and 15s will clear an 11" rotor. In general.

If the Compass as the stock steel wheels (that may be 15"), the OP can be sure they're the smaller rotors.
 
I wonder if the FWD uses the smaller rotor, and the AWD uses the big one?

Biggest rotor I have seen in a 15" wheel is 11.75".
 
Originally Posted By: Throt
I had him measure them. 11.9" on all 4 wheels. Not sure what size wheels it has though.


11.9x25.4=302mm
 
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