I'm not sure if this would go into the "modified" gate, but since I am going to use brakes that aren't factory, I figured why not. Mods- feel free to move if needed.

I have an 07 JKUR. I've heard and read that the factory master cylinder and booster are not that great, and they were upgraded I believe in '11? Is this actually the case? If it is, could the booster/MC from a '11 and up JK simply be swapped over to the '07?

I have the Teraflex performance brake kits f/r (larger rotors, uses factory calipers), and a set of SS brake lines from Crown Performance. Do I NEED to upgrade my booster/MC? I'm interested in the J8 conversion, but those have been on national backorder for forever and a day now. I'm planning on running 35's in the future, which is why I'm doing a brake upgrade. TIA for any help y'all!

 

They work fine on my 07 JK with tons and 40's

 

What size tires are you running now? If you are planning on going with 35's I'm assuming smaller now? Those TF big brakes should have no problems stopping a smaller tire with the factory MC.

My current setup running 37's on heavy beadlocks using Dynatrac Progrip brakes and it stops like a dream using the factory MC.

I'm not aware of any changes done to the master cylinder post 07 so kind of curious on that but my 1st JK which was an 07 seemed no different when stock than my current 15..

 

Brakes are pretty subjective. What some people think is fine others might think suck. Are you ok with the way the brakes feel right now? You're not changing anything in the BB/MC/caliper equation so the pedal is going to feel the same as it does now. The larger rotors should be plenty to stop 35s as Ryan suggests.

My understanding has always been that the newer MC has a bit larger bore than the old ones, but I also think that my thought process is based primarily on old TF literature with their BBK and them saying that on the pre-'11 models you should upgrade to their TF MC while the other models you were fine as they already had a larger bore in the factory MC. (ie, I haven't done some deep dive with all sorts of numbers and facts to back things up).

I'm using dual-piston calipers paired with TF rotors and factory BB/MC on my '13. Many people would say those calipers would require a larger MC but I find the factory set up to be fine for me, granted I'm not out driving like I stole it. On a side note, I tried the J8 kit a while back and didn't have luck with it. Blew the seals in two MCs real quick and was done jacking with it....went back to factory BB/MC.

When you move to 35s if you feel like you need to upgrade, then consider the J8 kit. I bet you're fine as is.