Hello All! Thought I would contribute to the forum. I have a 2017 JKUR with steel bumpers, metalcloak 3.5" lift, 35's aev wheels with teraflex rear carrier, rock hard full under skids... the JK is mostly overland type use. The JK feels really heavy and never liked the feel of the brakes (even in stock form). I come from the world of P and M cars so I'm spoiled. This is my 2nd JKUR and they both feel spongy when it comes to hard and emergency braking. I've installed the Mopar P5160050 setup with stock brakes and bled the system using the motive power bleeder. The install was pretty easy as long as you free up space for the new master cylinder by loosening and moving the abs tray and windshield wash tank forward. Also, freed up the horn and the 2 relays next to it so you can remove/install the brake booster easier. The master cylinder was bench bled and bled again at the 2 flange nut brake line attached to the MC. The original booster check valve was reused and the vacuum sensor attached fit with no issues. When the booster rod was attached to the brake pedal, the brake switch reseted (automatically adjusted) to the new length since the rod was longer. I have been driving with the bigger brake booster and master cylinder for 2 weeks now... and the feel of the brakes have greatly improved! It also brakes harder with no spongy feeling to the point I can make the tires squeal.... I have never experienced that with any of my JKUR with the stock setup. I believe that with upgraded brake pads and the Mopar P5160050... it is a good improvement over the stock setup. So far Im happy with this upgrade!


Next Up, I have the crown BBK front and rears... In another week or so, I plan on doing the rears, drive it for awhile and follow up with the fronts... Ill keep you updated. LET ME KNOW what you guys think.

 

Crown bbk rears? I thought those were discontinued a long time ago?

 

No, I believe they came out recently...
https://www.quadratec.com/p/crown-automotive/rt31057-rear-big-brake-kit-wrangler-jk


Here are the fronts
https://www.quadratec.com/p/crown-automotive/front-big-brake-kit-wrangler-jk-rt31046


and the Brake MC and BB... I got lucky and snagged one on Amazon.
https://www.quadratec.com/p/mopar/br...-axle-P5160050

 

Very nice. In my V8 conversion I ended up with an oil lubricated vacuum pump driven off the engine so with the carbon fiber pads I used and this extra vacuum I have not felt the need for better brakes after these changes but may consider a BB kit at least for the fronts in the future. I do realize that the discs will wear down faster now but they are not that expensive to replace.

 

Is that vacuum pump tied in with the engine vacuum system or is it isolated/parallel to the booster?

The thing I noticed with the new bigger MC and BB is that the pedal stroke is much shorter travel, more progressive and brakes harder... honestly, the more I drive, the more I can daily drive this setup. However, on emergency/hard braking... I do feel the brakes fade nearing where the jeep is about to stop... That's where the stock calipers falls short (gets heat soaked quickly). I think a lot of people will be happy just with the Mopar P5160050 setup and stock brakes.

Edit: As for emergency/hard braking, the brake fades are at speed of 65mph... so, I guess with all the weight of the jeep, I was not surprised.

 

That vacuum pump is mounted by Chev and uses oil pressure from a boss on the block. It only goes to the booster. It was for the engines that have Active Fuel Management that run V4 which causes low vacuum. I turned the AFM off which took about 30 seconds.

 

Sixty4X4... that's a pretty slick idea, plenty ways to skin a cat!

I've seen a few people on the net damage their MC because they didn't insert BB push rod inside the MC shaft. If the BB push rod is not inside the MC shaft, when they step on the brake pedal, the push rod slams into the MC seal and destroys it. A simple check that the BB rod is inserted in the MC shaft (before mounting the MC to the BB) is the to move the MC side to side. You should be able to feel and hear the BB push rod against both side of the inner wall of the MC shaft as you move it side to side. Once you know the rod is in the shaft, you can mount the MC to the BB. Again making space for the MC so that you have a descent angle to mount it is key.

 

Redridge - yes it is a good system but I am thinking you thought I added the pump to a Jeep engine but I have the Chev engine in my Jeep so the vacuum pump came with it and is used for brake vacuum as that is the only way it will work the booster.

 

Ok, so I have been running with the bigger BB and MC for awhile now and this is a noticeable upgrade with the stock oem brakes. If I had to spend the least amount of money on brake upgrades... THIS IS THE ONE! I know these are hard to find but I highly recommend getting one or two... for a friend. The brakes stops harder with better progressive feel (the harder you step on the brake pedal, the harder it stops). Its alot easier to modulate the brakes now... before with the stock setup, there was no feel at all and often have to pray that you would stop on time. Not with this setup, I find myself stopping way before than expected. There is one drawback though... it eats pads quick (especially the rear). I have no idea why, since its apparently front biased brakes. I put on new powerstop pads on and its already halfway done with less than 1500 miles on it. I admit I've been pushing these brakes hard though (for testing purpose). For daily driving and confident inspiring braking... the Mopar P5160050 is the ticket (keep an eye on your rear brake pads though).


So the next phase is to upgrade to the bigger rear rotors hopefully it doesn't eat pads like the stock setup since the rotors is much bigger, hence better braking torque. We'll see shortly.


Also, my calipers were filthy, this is a good time to paint them.

 

First day impression? Save your money, not worth the very small performance. It may save pad life in the long run though. (time will tell). As for the Crown fitment... it kinda sucks. The bracket did not center on the rotor, I say 1/4" off center line. The bracket doesn't seem to rub on the rotor but the pads will wear uneven (we'll see). The pedal feel seems the same but the I don't see a drastic difference between the stock setup. Will drive for a week or so and see if it grows on me.