View attachment 3549
So I can’t find specs for XR-only brakes. Next time I’m in the parts dept. I’ll pull up the part numbers for an XR. I suspect that it is the same as the non-XR because Jeep would want to keep the parts supply simple and reduce costs. I did find specs for the non-XR regular 392, the 4Xe and the regular Rubicon/Sahara. What it shows is that all 3 get the same front brakes, but the 392 and 4Xe get larger upgraded ventilated rear brakes. That makes sense because most of the stopping force is the front brakes and Jeep doesn’t want to kill paying customers (even Sahara owners
)
So the
non-XR 392 has:
Front Brakes:
12.9 x 1.1 (330mm x 28mm) vented rotor
2 (51mm) twin-piston floating calipers
Rear Brakes:
13.6 x .86 (345mm x 22mm) vented rotor
2 (51mm) single-piston floating calipers
That is basically the exact same brakes as the
4Xe which also has:
Front Brakes:
12.9 x 1.1 (330mm x 28mm) vented rotor
2 (51mm) twin-piston floating calipers
Rear Brakes:
13.6 x .86 (345mm x 22mm) vented rotor
2 (51mm) single-piston floating calipers
Just for curiosity the regular
Rubicon and
Sahara have:
Front Brakes:
12.9 x 1.1 (330mm x 28mm) vented rotor
2 (51mm) twin-piston floating caliper
Rear Brakes:
13.4 x .55 (342mm x 14mm) solid rotor
1.88 (48mm) single-piston floating caliper
I am sure the brakes could always be better:
- Larger/more pistons, staggered pistons
- Larger rotors + calipers = larger rims
- Better rotors with more ventilation
- Red painted calipers (Red stops way more better… )
I would really appreciate any pictures of XR brake part numbers including the master cylinder so I can look up specs on those parts.