Brake System Upgrade Question


Caught the Bug
I am nearing completion in parts accumulation and upgrading a set of Rubi axles and am now turning my attention to brakes. I am planning on going with the Crown front Big Brake system and another big brake system for the rear - not sure which one yet. My question comes from observations that others have had issues with the J8 master/booster combo with seals consistently blowing out between the master and booster. I have also read the upgraded master/booster is not necessary on 2012's such as my JK. I have further read that those who have done an LS swap that includes the GM oil driven vacuum pump see much better braking performance and especially peddle feel.

So, now my question:

Would there be any benefit to adding a vacuum reservoir to support the stock JK vacuum pump?

I understand that earlier Wranglers had such a reservoir, but I am assuming this is because they did not have a vacuum pump and that these went away when Jeep added the vacuum pumps to the JK. Given the experience those have with the seemingly "better" GM vacuum pump I started wondering if a reservoir would help or is it less about vaccum supply and more about PSI suggesting the reservoir would probably not help. I have tried to research this on our foroum and accross the internet and can find no posts anywhere about if there is any benefit or danger to adding a reservoir.


Caught the Bug
Since you are running rubicon axles I assume that you are going to be sticking to a 37 and smaller. I can't add anything about the crown, but before I upgraded axles I ran pretty heavy 37x13.50x17 toyos on KMC Machetes with the dynatrac pro grips (not a light set up) It was front and rear for right around $1000 and worked really well with the stock res and master cylinder. It would solve the dilemma about the rear and if you are apprehensive about the J8.
FWIW I have the J8 booster/MC/Res for a while and haven't had problems. Just my two cents. I'm sure some of the other guys will chime in too.


Caught the Bug
I ha e no experience with the setups you're asking about. But to echo KevinG's comment, I'm running Pro-Grips all the way around with Hutchinson beadlocks with 37x12.5/17 Toyo MTs there's plenty of stopping power with them for sure, around $1k for all 4 corners
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Caught the Bug
Thanks for your replies and suggestions!

My current plan is to go no larger than 35s on the Rubi axles given the fragility of the front axle in particular. My plan eventually is to either: 1) upgrade the front to a PR44 and regear the rear D44 and go no larger than 37s and build a rock buggy for the really crazy trails; or 2) upgrade to a PR60/PR80 and go crazy (e.g., LS, 40+ tires, etc.). However, these are - at this point - really long term plans (e.g., I won't likely go to Dynatrac for at least another 5-10 years when I retire hopefully to the mountains of Colorado). Really, all I am wanting to do right now is to evolve the Jeep to a level just a little above a Rubicon. This is because I have very little experience off-roading and I do not want to give myself more confidence in my machine to "bail me out" than I have skill to back it up. In my few experiences on Badge of Honor trails I have been amazed at how capable my stock sport on 33s has been, and figure almost all other Badge of Honor trails will really only require something at or just above the level of a Rubicon. I like to use BOH trails and the reviews of these trails from other JK owners to gauge my progress in gaining off-road proficiency, which is why I keep mentioning the program. Well, and I like the badges too as a way of showing my Jeep isn't just a "Mall Crawler"! LOL

Looking at the Pro-Grips vs Crown Kits: It seems like the majority of the price of these kits is for the brackets. New rotors can be had for $75 for the Crown and $100 for the Pro-Grips. Pads are around $120. The Crown's do come with Ram dual piston calipers for the front. I assume these are better than the stock JK calipers, but may not be entirely necessary given rotor size contributes much more to stopping power. Decisions decisions!
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