I upgraded my 90 MJ with a booster and master cylinder from a 95 or 96 XJ. Great results.
I now need to do the same to 3 Renix Jeeps in the family.

Besides the 95 to 96 XJ swap, what else have you guys had success with? 95 to 96 is slim pickins in the JY.

 

What's the difference between this and the ZJ swap? Is it just the spacer, or is there a functional difference/ benefit as well?

 

That's what I want to know. The 95 to 96 was cake.

ZJ, WJ? Either one work well and how simple? I don't care about making brake lines....

 

I have the wj booster and master on mine the only thing I did was cut the pinch seam and hammer it a bit, ground down the rod and drilled a bigger hole for the spacer. I had some problems at first with the brake lights either staying on or not working. It stops a lot better then what it did before, the only thing I have noticed it will lock up very quicky in the rain with sometimes, with the slightest pedal movement. But then again it could just be my set up also.

 

make sure your rear brake cylinders arent leaking thats what my rears did when they leaked

 

I got my donor from a '96 also. Piece of cake, no modifications needed to the firewall pinch seam. I called the jy and they had another too, $50. I can see why they would be difficult to find. The only thing I had a problem is grinding the round brake pedal rod so the brake switch works. I would have rather had the old rod installed in the new dual diaphram booster.

 

The rod and brake switch doesn't bother me. That went fine.

hbracing, was there a 1/4" spacer made of aluminum between the WJ booster and firewall?

The 95 and 96 come with the spacer and pedal height is perfect.

How was your pedal height? Did it change?

 

Nope there was not a spacer for the wj, not that I remember anyways. I don't think it changed but I didn't really pay attention to it, I was glad just to have better brakes then what I had before.
I know for the zj and xj from 95 to I think 97 they had the spacer then it changed again. Something to do with the rod.

 

I think that's why you had to modify the pinch seam. Pedal height higher than before?

 

Did the WJ booster on the 88 yesterday.

Easier than the 95 to 96.

ZJ flat doesn't work.

WJ has flexible lines off the master cylinder and you don't have to move the washer bottle. Pedal height is perfect.

 

dode durango master cylinder with the later xj booster

the durango MC has a .25 larger bore and is bolt in

 

Good to know. I'm only on 31s with no plans to go bigger. Also have rear discs.

 

So cruiser would you do the WJ booster again? I'm getting sick of stock brakes and 35s. I'd do rear disc but I don't want to buy e brake cables right now and since its a 5 speed I use it all the time. Also, what years did that master cylinder from the Durango works best

 

What about booster/mc upgrades for a 99 xj?

 

Not much help for '97+.

Hydro booster, 1 1/8" Durango master cylinder but the problem really is just too small of brakes. Fine for stock. Less for bigger tires and added weight.
Better pads-IDK Black Magic etc, ZJ rear and WJ front upgrades, Vanco, other bigger brakes.