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Booster Upgrade

mgracer

NAXJA Forum User
Location
Petersburg, MI
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!
 
95-up XJ, ZJ, should be plug n pray. WJ booster will work as well

There may be a write up on here somewhere
 
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).
 
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.
 
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.
 
All of this relocation and the like is exactly why I'm going hydroboost!
 
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.
 
Not a huge fan of hydroboost, lose power steering and lose brakes... I've lost power steering many times

That simply isn't true.
 
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
 
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
 
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.
 
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…..
 
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