What about the brakes?

switz

Active member
Founding Member
Joined
Jun 5, 2021
Messages
43
Reaction score
96
Location
95959
Current Rides
2024 392 on order, now delivered! (had a 21 392, traded it for a Bronco Raptor and am going back to a 392)
I have a 392 on order and it is scheduled to be delivered in the middle of August. I have seen some YouTube videos regarding the brakes and upgrading them. The link below is from a guy who just upgraded them to a Big Brake Kit from APB. Looks like an easy upgrade and looks like it provides substantial improvement in braking performance. One thing to note, especially if you are going to be getting new rims and tires, make sure you get 18" rims or you will need a spacer.

 
hopefully someone else makes a kit that we dont need spacers for
 
what so bad about spacers? i have them on most of my cars have never had an issue to date and i have spacers and teraflex delta's waiting for my xr due in next week.
 
what so bad about spacers? i have them on most of my cars have never had an issue to date and i have spacers and teraflex delta's waiting for my xr due in next week.
Spacers need to be torqued regularly so they don’t come loose. They also add addition stress to the axles by spreading the load out wider, but that is not much different than decreasing your rim backspace.
 
I have a 392 on order and it is scheduled to be delivered in the middle of August. I have seen some YouTube videos regarding the brakes and upgrading them. The link below is from a guy who just upgraded them to a Big Brake Kit from APB. Looks like an easy upgrade and looks like it provides substantial improvement in braking performance. One thing to note, especially if you are going to be getting new rims and tires, make sure you get 18" rims or you will need a spacer.

I'm curious about this as well. Are there any after-market break upgrades that don't require spacers? How often do spacers require maintenance?
 
I opted to switch out the stock brakes as I felt the factory setup was just not adequate. I choose brakes over the factory wheels...Installed the Terra Flex Delta Brake kit. Brakes are designed pretty well with four pistons per brake. Also comes with 14 inch rotors. On the negative/downside, brakes require 4.75 inch back spacing at a minimum, so if you want to keep the factory rims, you have to install a spacer for rotor clearance. I installed the Terra Flex 1.75 inch spacer. Ran the Jeep like that for a couple of weeks and just did not like how the Jeep drove. Opted to purchase news wheels (stayed with 17 inch rims but with the proper off set) and tires.
I also opted to go with a setup that gives me the most on street drivability.
‘Setup prior had 35 inch tires dropped down to 33’s. Drivability is superb and much more enjoyable to drive as the 392 is my daily driver. Setup works for me...
Have you noticed a substantial difference in braking power?? I want to upgrade my brakes, but I also want to keep the stock wheels. :(
 
The XR has an additional brake supplement. I’m comparing my 2021 RAM 1500 Limited that has much better braking than my 392, and actually weighs more.
 
I opted to switch out the stock brakes as I felt the factory setup was just not adequate. I choose brakes over the factory wheels...Installed the Terra Flex Delta Brake kit. Brakes are designed pretty well with four pistons per brake. Also comes with 14 inch rotors. On the negative/downside, brakes require 4.75 inch back spacing at a minimum, so if you want to keep the factory rims, you have to install a spacer for rotor clearance. I installed the Terra Flex 1.75 inch spacer. Ran the Jeep like that for a couple of weeks and just did not like how the Jeep drove. Opted to purchase news wheels (stayed with 17 inch rims but with the proper off set) and tires.
I also opted to go with a setup that gives me the most on street drivability.
‘Setup prior had 35 inch tires dropped down to 33’s. Drivability is superb and much more enjoyable to drive as the 392 is my daily driver. Setup works for me...
I was considering this teraflex set earlier. Didn’t know it would require spacer. Thanks for the information and pics.

Do you feel the new brakes more responsive and give you more confidence? I’d assume the stop distance may improve.
 
I have a 22 XR and my brakes seem just fine. What’s all the fuss about?
Waiting for my XR to be delivered to dealer. For me, I was hoping the 392 would come with brembo breaks like the GC SRT initially. That’s why I started looking at better ones. Then I told myself that new breaks should be good anyway, might just do the upgrade later or maybe not. On the other hand, the driver is the key of safety. I tend to break a bit earlier and allow enough distance, hopefully.
 
The XR has an additional brake supplement. I’m comparing my 2021 RAM 1500 Limited that has much better braking than my 392, and actually weighs more.
I have been trying to track down what actual upgrade of the 392 XR brakes is over the 392. The only information anywhere about the brake upgrade is a post in Facebook. There is no part number differences for the XR that I can find.
 
Brakes much improved... better pedal response, and less foot force on the pedal - pretty simple math, 8 pistons versus 16. Brakes were OK before, great now. Crazy fast Jeep, combined with lots of stupid drivers; having the best brakes possible just makes sense in my area.
Current 392xr brakes are much better than my jk on 37s. Happy with stock brakes for time bEING.
 
Brakes much improved... better pedal response, and less foot force on the pedal - pretty simple math, 8 pistons versus 16. Brakes were OK before, great now. Crazy fast Jeep, combined with lots of stupid drivers; having the best brakes possible just makes sense in my area.
So you are saying the 392 vs 392xr has more piston calipers? That is totally not the case. It is amazing what is said And believed as truth on a forum.
 
Imo brakes are more than adequate... they just lack "feel". A set of braided brake lines would give you the feel you're looking for without going crazy on a completely new set up.
Its worth a shot
 
I have been trying to track down what actual upgrade of the 392 XR brakes is over the 392. The only information anywhere about the brake upgrade is a post in Facebook. There is no part number differences for the XR that I can find.
0A936E33-42A8-49C2-8A6B-EE61DB92FACB.jpeg

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 :p)

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.
 
Last edited:
Just an observation but with 17” rims I dont think the rotors can be any bigger than they are now. As it is the caliper housing is very close to touching the inside of the wheel.
 
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 :p)

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.
The XR is the same physical brakes, but it has a "brake booster" that I believe is vacuum controlled.
 
Just an observation but with 17” rims I dont think the rotors can be any bigger than they are now. As it is the caliper housing is very close to touching the inside of the wheel.
Yeah I think that’s the limiting factor.

Larger rotors + calipers = larger rims

And that is another reason I don’t think the Xtreme Recon has “upgraded” brakes. The wheel diameter is still 17” the difference is in the wheel width; 8” for the XR and 7.5 for the regular 392.

I like the OEM wheels personally. When I upgrade from the stock 33” BFG KO2 to a 35 inch tire I might combine that with upgrading the brakes. I would look at Brembo, Wilwood, or Baer. I know Baer makes a 13.5” (342mm) 3-piston front brake (and it come in RED! 😀 Just like stop signs and stop lights and those stop stuff real good!)

But for now the MOPAR “big brake kit” will work, at least until my bank account recovers.🤣
 
Last edited:
Back
Top