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mgracer
October 9th, 2017, 20:57
I have a '91 Cherokee and have removed the goofy booster & master cyl.
Exactly what year & model Cherokee has the parts I need to upgrade my brakes & be as bolt-in as possible? I have read a lot of conflicting ideas & would like to know what works best. Thanks!

Johnnie Walker
October 9th, 2017, 21:32
95-up XJ, ZJ, should be plug n pray. WJ booster will work as well

There may be a write up on here somewhere

clydefrog
October 9th, 2017, 21:46
I did a WJ booster and master on my Renix XJ. I did make a 1/4" spacer for mine out of steel so the brake pedal would sit in a good location (cant remember if the spacer was necessary though). other than that it was plug and play. Best brake mod I have ever done!

I also added a Willwood adjustable proportioning valve to dial it in (that was def NOT plug and play).

ehall
October 9th, 2017, 22:05
95-96 booster is essentially bolt-in compatible (97-up has different pedal setup). If you upgrade the MC at the same time you will need to change the ends of the short lines that go to the distribution block to metric bubble flare. WJ upgrade is also compatible but you will need to clearance the pinch seam on the firewall to have room for the booster.

Francesco
October 10th, 2017, 08:19
I did the WJ swap on a '90 Renix. No spacer needed, but slight clearancing was required. If I remember correctly, however the newer XJ booster required a windshield reservoir relocation.

burntkat
October 10th, 2017, 09:16
All of this relocation and the like is exactly why I'm going hydroboost!

mgracer
October 10th, 2017, 09:48
Burntkat, please tell me more about the hydroboost.

mgracer
October 10th, 2017, 10:16
Should I get a booster, mc, prop. valve, & pedal assembly from a '96 Cherokee or a '98 Grand Cherokee?

Green XJ Jeep
October 10th, 2017, 13:02
Dual diaphragm from a 95-96 XJ is you best option for an easy bolt on.
WJ will work but need some modifications.
If you go the WJ route make sure you get the brake lines from master cylinder to proportion valve. You will need the ends to make new lines.

Francesco
October 10th, 2017, 14:46
Not a huge fan of hydroboost, lose power steering and lose brakes... I've lost power steering many times

burntkat
October 10th, 2017, 15:03
Not a huge fan of hydroboost, lose power steering and lose brakes... I've lost power steering many times

That simply isn't true.

Francesco
October 10th, 2017, 15:17
That's how it worked on my buddies excursion when we lost the power steering, are there different types of hydro boost?

Green XJ Jeep
October 10th, 2017, 16:02
That's how it worked on my buddies excursion when we lost the power steering, are there different types of hydro boost?
The newer ones will have am electric motor back up.
Its been my experience that while the back up does indeed work it doesnt work that well.
Bracking performance is about the same if you stall and have no vacuum going to a vacuum booster

spidermikey88
October 11th, 2017, 19:14
I did the wj booster and master cylinder upgrade on my 87 and it made a huge difference. But like the other guys have said, you have to do a few modifications to make it work. I think it was worth it though and I'm about to do the same thing to another xj I just picked up.

Sent from my Pixel using Tapatalk

mgracer
October 12th, 2017, 07:59
Spidermikey88, what mods did you have to do?

1990JEEPXJ
October 12th, 2017, 12:06
All you should have to do is bend and flare some lines. The washer bottle does not need to be moved to fit the WJ booster on a Renix.

cruiser54
October 17th, 2017, 06:42
WJ versus 95 to 96 XJ booster

Actually, the WJ booster is in some ways easier than the 95 to 96 XJ.

I've done both.

XJ, you don't have to mess with the firewall. No big deal anyway.
But, you have to move the washer reservoir. And, once the original booster comes out, the bracket inside the cab moves and makes it a bear to install the new booster.

WJ you have to bend or cut the firewall lip, but don't move the washer bottle.
As an added bonus, the mounting studs of the WJ booster are a bit smaller and it's easier to get in.
Another bonus with the WJ is that it has FLEXIBLE lines from the master cylinder that make putting things together MUCH easier.

And, WJ boosters are newer and easier to find…..

mgracer
October 19th, 2017, 10:12
Does one work better than the other?

Johnnie Walker
October 19th, 2017, 14:20
Does one work better than the other?6 of one, half dozen of another.

mgracer
October 19th, 2017, 17:17
Pushrod issues with either one?

Green XJ Jeep
October 19th, 2017, 19:10
Pushrod issues with either one?


When I did the WJ on my 89 I had to open the hole up a little bit and grind a flat spot for the brake light switch.
Lots of videos on the swap.

comanche91
October 19th, 2017, 19:48
WJ versus 95 to 96 XJ booster

Actually, the WJ booster is in some ways easier than the 95 to 96 XJ. I've done both.

Perhaps this is true if you are doing the WJ upgrade on a Renix. But for the 91 and up HOs, the 95/96 XJ swap is by far the easiest. Using the 1/4" spacer behind the booster, no firewall mods are required, and the firewall holes are correct for the four booster mounting studs. It's pure plug and play, even with the brake switch wiring. The only thing that's different are the two brake line fittings on the master cylinder you have to plumb in. And if your windshield washer tank is still in the stock location, it may have to be moved forward a bit if you don't make tight bends on the master cylinder lines. A two hour job max, even with bleeding.

cruiser54
October 19th, 2017, 22:11
Does one work better than the other?

The 99 to 2004 wJ works better in my experience.

mgracer
October 21st, 2017, 22:05
Got the 96 booster & mc & prop valve in. Should I use the 91 or 96 prop valve? Also, what do I with all the wiring left from the old system? There are plugs everywhere! And my battery went dead. Any relation to unplugging all the old brake stuff?

comanche91
October 21st, 2017, 22:24
Also, what do I with all the wiring left from the old system? There are plugs everywhere! And my battery went dead. Any relation to unplugging all the old brake stuff?

What wiring? A 96 booster/master swap on your 91 requires no wiring changes. Did (does) your 91 have ABS?

ehall
October 22nd, 2017, 08:27
Should I use the 91 or 96 prop valve?
I don't think there's any difference between them but I don't know about ABS for certain. They are not different for non-ABS. The flared fittings on the new MC are different and will have to be changed.

Also, what do I with all the wiring left from the old system?

Pull the ABS fuses and relays from the PDC box and ignore the wiring

mgracer
October 23rd, 2017, 08:00
The 91 had ABS. I got the proportioning valve with the 96 mc & booster & left it hooked up. I am just going to hook up the lines to the wheels & try it. Thanks for the help everybody!

BenWheelin
October 24th, 2017, 09:04
The newer ones will have am electric motor back up.
Its been my experience that while the back up does indeed work it doesnt work that well.
Bracking performance is about the same if you stall and have no vacuum going to a vacuum booster

That pedal feel, though.

To each their own.

Starboard M
October 26th, 2017, 12:12
Spidermikey88, what mods did you have to do?

http://naxja.org/forum/showthread.php?t=983426
:cheers:

muddypunk
October 26th, 2017, 17:06
I did the wj booster and master cylinder upgrade on my 87 and it made a huge difference. But like the other guys have said, you have to do a few modifications to make it work. I think it was worth it though and I'm about to do the same thing to another xj I just picked up.

Sent from my Pixel using TapatalkWhat did you do about the prop valve?

Sent from my XT1609 using Tapatalk

spidermikey88
October 26th, 2017, 17:36
What did you do about the prop valve?

Sent from my XT1609 using TapatalkI kept the original prop valve and then took the brake lines from the WJ master cylinder and had the fittings replaced on the prop valve side. I still have drum breaks in the rear so I didn't want to use the WJ's valve. I can take some pics tonight if you want to see any it.

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muddypunk
October 26th, 2017, 17:37
I kept the original prop valve and then took the brake lines from the WJ master cylinder and had the fittings replaced on the prop valve side. I still have drum breaks in the rear so I didn't want to use the WJ's valve. I can take some pics tonight if you want to see any it.

Sent from my Pixel using TapatalkThat would be awesome I need to figure out what to do on my MJ.

Sent from my XT1609 using Tapatalk

spidermikey88
October 26th, 2017, 21:51
That would be awesome I need to figure out what to do on my MJ.

Sent from my XT1609 using TapatalkFirst I had to bend the pinch seam at the firewall up a little so it could fit the larger booster
https://uploads.tapatalk-cdn.com/20171027/c4633567362d81d58c07496abb289632.jpg

Then I took the brake lines from the WJ master cylinder and had the fittings going to the proportion valve redone so they would fit my old valve.
https://uploads.tapatalk-cdn.com/20171027/237875e08e576248be2b4cb76f073078.jpg

https://uploads.tapatalk-cdn.com/20171027/e66c15e62c686a40bb5750236b5b2fe1.jpg

The hardest part for me was the brake light switch though. I ground a little too much off the end of the wj pedal rod and that made the brake lights only come on when the pedal was about 70% of the way down (mines an 87 and I think the switch was changed in 90-91 to one that would have made this much easier). A lot of people say to grab the whole pedal assemboly from the WJ and swap that in too - which is what I will do next time. I ended up having to make a bracket that held the switch at the right angle and distance from the pedal arm.
https://uploads.tapatalk-cdn.com/20171027/baf3a1acf126ff5982364abf5fa29c12.jpg

I paid about $35 for the booster, master cylinder and the brake lines from pick and pull and $10 to have the fittings replaced at a local shop. Overall, I'd say it's worth it and i plan to do it again.

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muddypunk
October 26th, 2017, 22:20
Sweet I have a new booster for my grand that was totaled in December. Thank you I'll be sure to grab the pedal and light assembly.

Sent from my XT1609 using Tapatalk

XJ firetruck
October 30th, 2017, 16:16
mgracer, have you been able to get time to complete
the swap?