I'm curious what the actual benefits are for something like this. I have a 94 with a rear disc brake conversion (8.8 from a ford explorer) and larger front discs (from a 80s chevy to go with my D44 swap). I still have the single diaphragm brake booster and stock master cylinder. I've been running 35s for a while now and have never seemed to be in want for braking power. I can even lock up all 4 at highway speeds.

I always thought that the limiting factor in our braking system was the rear drums and single piston front calipers on tiny rotors, not the single diaphragm booster or small master cylinder... am I wrong?

 

The XJ MC is 1" and the Durango is 1 1/8".

Master Cylinders for XJ/TJ-
1" bore, Stock XJ, F-12x1BBL, R-10x1BBL, rod 2.12" Centric #130.67018('98 Cherokee)
1.0625" bore, some '99-03 Durangos, hit or miss, *must check*, same fittings
1.125" bore, '03 Durango, Viper, Cardone #132967, Dorman #M630162, same fittings
1.125" bore, '03-'10 Viper, '99-'04 Dakota, '99-'01 Durango, Centric #130.67025 premium, #131.67025 C-TEK standard
1.250" bore, Dodge 1500, 2500, 3500 pickup, Centric #130.67023, same fittings, pressure rod 1.09"(will need to lenghten rod)

 

When you are talking about the miniscule amount of fluid that actually moves when you apply the brakes, 1/4" is a HUGE decrease in braking pressure................


Most people who do the WJ brake swap, do it as an upgrade in braking performance by keeping the stock XJ 1" master cylinder.........


This is one instance where bigger is definitely NOT better!

 

So my buddy asked me to do this to his 5 inch lifted 2001 XJ with 32s so I got a Durango MC at a JY for $15 and installed it.
Direct fit, took about 20 min to include bleeding the brakes.


He says it is night and day. He has a Quadratec rear disc kit and he was trying to make the braking more responsive.


I really didn't notice much but then again, I never drive his rig and mine is running on stock tires with a ZJ rear disc install.

 

Thanks for the info. More braking power is never a bad thing.

 

My 89xj I can do this all I need is a booster from a 99 xj and that should fit no prob and the rod is correct and everything attaches to that and then just buy a master from a Durango and it's good? No Change needed for proportioning valve? I got drums now going to a ford 8.8 with disc soon but I'd like to do this before the axle swap?

 

No.

You need to do the 99 to 2004 WJ booster and master swap first.

Then, if you feel the need, you MAY be able to change master cylinders to the Durango one.

 

ok thanks

 

I've done 95 to 96 XJ and 99 to 2004 wJ swaps into Renix era XJ/MJs. I MUCH prefer the wJ swap.

I can guide you through it.

I've got another one to do. Maybe I'll do a write-up?????

 

that be great. looking to do the swap just wasnt sure if i should do it before or after i do my 8.8 swap

 

8.8 with discs?

Don't matter.

 

You should do another write up....could add it to the "book"

 

#28, huh?

It's such a worthwhile mod, I will do a write-up.

 

yes please do.

 

Slave drivers!!!!