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brake system... unfortunately mine xj is '90

stefanoquinto; My '89 cannot go with big tires like you want. Why? Because the wheel bearings are too small in width, and the additional pressures of big tires, or even wheel spacers, (for a wider stance), will eat the wheel bearings prematurely. Now I am not certain, but I think, a guess, that '90 XJ's have the same wheel bearings. I hope someone will verify one way, or the other so you do not cause unwanted damage. Do you have a lift kit installed to warrant the use of 33's? My kit is 2 inches lift, and I would go no higher than 29, or 30 inch tires, especially if you remove the rear stabilizer bar, and obtain a front stabilizer disconnect/connect kit such as JKS. Some say I could go with 31 inch tires, but I think that is just unnecessary, both for wheel bearing wear, and possible inner tire well contact. Keeping all wheels on the ground is good, and the disconnecting of the stabilizer bars will allow you to better keep them on uneven ground. The front stabilizer is reconnected, (takes just a few minutes), for safety on all flat higher speed road use. Good luck!
 
Alaskan89XJ said:
stefanoquinto; My '89 cannot go with big tires like you want. Why? Because the wheel bearings are too small in width, and the additional pressures of big tires, or even wheel spacers, (for a wider stance), will eat the wheel bearings prematurely. Now I am not certain, but I think, a guess, that '90 XJ's have the same wheel bearings. I hope someone will verify one way, or the other so you do not cause unwanted damage. Do you have a lift kit installed to warrant the use of 33's? My kit is 2 inches lift, and I would go no higher than 29, or 30 inch tires, especially if you remove the rear stabilizer bar, and obtain a front stabilizer disconnect/connect kit such as JKS. Some say I could go with 31 inch tires, but I think that is just unnecessary, both for wheel bearing wear, and possible inner tire well contact. Keeping all wheels on the ground is good, and the disconnecting of the stabilizer bars will allow you to better keep them on uneven ground. The front stabilizer is reconnected, (takes just a few minutes), for safety on all flat higher speed road use. Good luck!
Click to expand...
thanks for suggestion. now I've 2' with coil spacer in front and blocks in rear. rear i've been removed stabilizer bar and when use the 31' all are fine (more or less). before put the 33 i will do many jobs.... the 1st is the brake system....
 
I really want to start buying what you need to fix the jeep. But I can not decide. I supposee that the difference between the brake power booster of the Grand Cherokee and Cherokee could lie in the fact of not having to change the brake pedal, but I can not understand it well. I want use a dual diaphragm bosster.
 
I am doing the conversion on my 1990 XJ as we speak..... I have ABS and it freakin died last week and me not working at the dealer anymore I dont have the access to lifetime ABS actuator and pump replacement on the Bendix 9 ABS on the early XJ's easily...... I was told the ABS actualtor for the Bendix 9 is NS-1 which means Chrysler does not have anymore..... I could push it and have them get the ABS actuator and pump dealer to dealer but they wince at that as it costs them money to do that...and most dealers dont even want to touch the Bendix 9, let alone fix it under recall........ Some of the dealers even have the balls to sell the actuators and pumps on Ebay at full retail knowing they are a lifetime recall item..... So to make a long story short, taking out the ABS and it's going in the trash......

I am installing Grand Cherokee 1994 to 1998 ZJ non-abs master/booster ...it came with booster.master,lines from master to pro-valve and pro valve with cut off lines with fittings off the pro valve and bracket .....
Need to slightly bend up lip on firewall, remove the aluminum spacer from the ZJ booster if it came with one, take off ZJ pro valve and reuse your ABS proportioning valve......

I used a double flare tool and made lines from the lines off the ABS unit.... some of the fittings are standred and some are metric...you will figure that one out..... I used a brake line tee from the Old Abs unit and correct fittings and tied the front brake lines together...... then made a line for the rear brakes from proportioning valve to the original coupler on the line going to the rear brakes about 5 inches long....... you are going to spend some time getting the lines to the proportioning valve bent and cut and flared right, the proportioning valve has no bracket and you want it as far forward as you can get it so you can tighten lines etc....rubber capped end of the proportioning valve goes towards front of Jeep, front outlet on master cylinder is for rear brakes, rear outlet is for front brakes.... I did not have to buy any flare nuts or line, i had enough fittings and 3/16 inch steel brake line from the old ABS unit to make it work........

Make sure you get good lines from the master to the proportioning valve on the ZJ booster/master.... the lines that go into the master are bubble flare and not double flare.... not to easy to get tool to make bubble flares..... I am sure you could dig up male bubble to female double flare adaptor if needed to run double flare lines from the master.........

I also cut off the end of the brake pedal rod on the ABS unit and lined it up on the end of the ZJ booster pedal rod and clamped with vise grips, then took thebarrel carbide bit on my diegrinder to duplicate the hole and shape of the ABS rod for the brake light switch and pedal bolt and bushing on the ZJ pedal rod end......you could also use a 5/8 drill bit and a file to flatten the end of the ZJ pedal rod for the brake switch...........

I have the ZJ booster,master,XJ ABS propotioning valve and all lines built.flared and installed........

Tomorrow I have to remove the brake pedal and redrill the bolt hole for the brake rod to brake pedal, the hole in the pedal is to far up and makes the booster rod crooked and cant attach.....the Bendix 9 ABS pedal will not work unless you drill a new hole farther down the pedal or replace with Non-ABS pedal from 1987 to 1996? XJ........

Also I need to reshape the corner of the washer bottle with a heat gun closest to the booster..... with the booster being thicker the washer bottle will not fit with out modding it........

Extend wire for the pro valve switch also.....

Also need to remove ABS pump and lines from it from under the expansion bottle..... now i have an excuse to go to open cooling system since i have freed up space getting rid of the ABS pump and crap.......

And down the road I will remove the ABS ECM from under the backseat, all the ABS sensors at the wheels and play around with getting the e-brake indicator light to work...have no idea what indicator lights will work as in brake getting rid of the ABS.......



So I hope that helps a little bit....... so far its not to bad to do...... I have read the WJ booster/master and pro valve works good also...... I did the ZJ booster as I got it cheap....should stop pretty good I hope....... the Bendix 9 ABS worked awesome with my 35" tires.... I could stop on a dime..... I hope the ZJ setup will stop just as good.......

If you dont want to flare or cut lines, hit the junk yard and get the left and right front steel brake lines and the rear steel brake line and also the brake pedal from a Non ABS Jeep 1987 to 1994?

That would make it all bolt in and just a little modding of the ZJ brake rod for the brake light switch........
 
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i was advised no to use the ABS XJ prop valve as not all of the ports are used in the ABS system. so they may have gunk in there and be dirty. i grabbed one off of a non ABS XJ so i know fluid was always going through the whole prop valve. not saying its necessary but is cheap insurance IMO.

but like you said rags, something needed to be done to the pedal. i did a WJ booster swap and just drilled a new hole in my pedal for the booster rod.

and BE SURE TO BENCH BLEED THE MASTER CYLINDER!!! i need to do that again. my brakes are still very mushy
 
I reused the Pro-Valve off the Bendix ABS, just uncapped the plugged port and cleaned it all out, actually pretty clean........... I do have the ZJ one that came with the used ZJ booster, so if i ever go to rear discs I can swap that one in.......

I redrilled the brake pedal for the booster rod... Centered the rod in the booster and marked the pedal shaft..... I also drilled the hole off center to raise the pedal height as it seemed a little low for my taste if the hole was in the center of the brake pedal ..... it came out perfect, also my brake light switch works first try using the old abs rod end I cut off and used as a guide on the ZJ brake rod..... Well all buttoned up......

I spent a little time and removed the ABS contoller from under the back seat, the ABS pump and lines..... all I have left are the wheel speed sensors ...just gonna leave the sensors in and cut the wires at the sensors and where they pop through the floor pan under the rear seat to keep the holes plugged up.........

Also got rid of the Anti-lock light and fixed the parking brake indicator light which dont work with the ABS module removed........pretty simple..........

I pulled what is called the yellow abs light relay...... Mine was right under the resistor for the fuel pump............
that turned off the Anti-lock light....pulling the 2 amp fuse in the fuse box for the ABS dont do nothing I could see..... left it in.....

And to get a working brake light indicator on the dash when you pull the ebrake all I had to do was go to the larger ABS controller connector under the rear seat and use a scotch-lock to tie C5 wire to C9 wire together..... one is blue wire and the other green...... walla, working e-brake indicator light...... also I hooked up the switch to the pro-valve..... uses the stock plug, just had to make the wires a bit longer....... in the ABS book the pro-valve switch is called a DPA switch...... it ties into the red brake light indicator also along with the ebrake like a non-abs system...... so have that working also........

All in all the conversion was pretty easy...just takes a little time with small details..... also got the stock windshield washer bottle to fit in the stock location...... took the heat gun to the part that hit the booster...... got it nice and hot and flexible, installed it hot and it molded itself around the booster.......pushed it against the booster passed the mounting holes, let it cool while pressing against the booster.....that gave me a little clearence between the bottle and booster....... it took me longer to get wires and hose to the rear pump run and postioned right....lol........

Will test drive tomorrow when the weather is a bit better......friggin raining and cold last few days........ anything below 70 degrees is cold! living in the Arizona desert has made my blood thin :)
 
please. can someone tell me if the pieces are the right ones?
I apologize if I ask stupid questions, but I do not understand everything you write. I write from italy and my English is really low.
for example I did not understand if I need the spacer or not.....
in the pic of booster that I've postet not seen.
thanks
 
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I've found this parts from italian zj 2.5L diesel..... whats U think?
7e10183dd7e097852740b27aca2758d3_big.jpg
 
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