THE XJ/MJ/ZJ/WJ master cylinder upgrade thread, what works, no questions.

[XJUSA]

I have done this 4 years ago. WJ brake booster and master cylinder with custom brake lines in my '91 XJ. I welded the old booster rod to new booster rod. May be that's , but no probs at all. Easy swap.

http://www.msctec.de/xjusa/projects/booster/index.html

[shmoken875]

Originally Posted by vetteboy79

There are hundreds of threads on this topic, but they all contain a huge amount of hearsay and uninformed responses, and the true tech gets buried.

I'd like to have a thread in which only people who have actually SUCCESSFULLY completed a master cylinder upgrade should post the following:

- Year/model of vehicle
- Year/model/style of booster
- Year/model/style of master cylinder
- year/model of proportioning valve (if used)
- Front brake configuration
- Rear brake configuration
- Overall performance

What we DON'T need is a bunch of people saying "I've heard you just swap in a E350 master cylinder" or "A 79 corvette MC works".

Sorry if this is a repeat, but I know I've been quite frustrated trying to find any accurate information on this, and I know there's some others out there with the same problems.

-98 xj
-stock dual diaphragm booster
-99 durango MC
-stock distribution block with o-ring removed (had to add advance auto adj. prop valve)
-front: waggy 44 (GM 1/2 ton calipers)
-rear: ford 9 inch (80 malibu calipers) [TSM MFG. kit]
-On 35s currently, stops a heck of a lot better. Not as firm as I would have hoped, but is MORE than adequate. Rear was locking up, so I had to knock it down a bit with the adjustable proportioning valve.

[vetteboy79]

Originally Posted by Bubba_Jeep

Would be useful to hear from you guys experimenting with late ('99 or newer) model Dodge (Rams and Durangos) MC's onto late model ('95 or newer) XJ/WJ dual-diaphragm boosters.

- 94 XJ
- 95 ZJ dual-diaphragm booster
- 1998 Dodge 2500 MC
- 95 ZJ distribution block (ABS removed)
- Large single-piston D60 calipers (front)
- GM 1/2-ton calipers (rear)

Much better than the stock MC on the same setup.

The Dodge MC bolts directly in place and seals properly; you need to extend the pushrod by about 5/8". I made a spacer to go in the pushrod bore of the MC. It's still a little too short but I haven't had the motivation to take it apart again.

The flare fittings are the same as the stock XJ so no cutting/reflaring is necessary.

Left to right:



'95 ZJ, '98 Dodge 2500, '94 Dodge 2500. I ordered the wrong Dodge one initially.



I forgot all about this thread.

[95steel]

91 MJ with stock booster. Ford 9 with drums, HP 44 disc with waggy calipers.

E-350 MC. Aside from the lines being on the wrong side of the MC it was an easy swap and it works well.

[Echo4charlie]

Originally Posted by Flashover Mfg

Stock 93 XJ booster
77 Mercury Marquis Master
Wilwood adjustable prop valve
78 F250 front brakes
77 Chevy K20 front brakes mounted to rear 14bolt
It'll lock up my 35s with ease.

-Joel

I have the same exact brake setup. Everything works well? No fade, nothing?

[Starboard M]

Small write up on the WJ Grad swap into a Renix XJ:

http://naxja.org/forum/showthread.php?t=924285

[blk88]

Originally Posted by vetteboy79

:

- Year/model of vehicle
- Year/model/style of booster
- Year/model/style of master cylinder
- year/model of proportioning valve (if used)
- Front brake configuration
- Rear brake configuration
- Overall performance

- '88 XJ, my heep.
- '96 XJ booster, MC and porp valve as donor junk.
- Stock front disc brakes.
- Stock rear drumb brakes.
- 37" tires
- Awesome performance

I don't know why I didn't do this sooner. I always wanted to get rear discs. After the swap I haven't even thought about it. The only issues I had was try to keep the porp valve in the location of the '96 with the bracket. By doing this I had to make new brake lines for the additional length. Also, I would have been able to keep the washer fluid tank in the stock location. My only issue was the rod. The '96 was round where my '88 has a flat end. I used my air grinder to make it flat and ended up taking too much off. I tack welded material back on and made it flat again unit the break switch worked. Not too tough, but a little frustrating. Overall, it was the best modification I've made after having 37" tires. I used to have to use both feet on the pedal if I had to stop on a steep hill. I'd still slip if it was steep enough. I can now stop anywhere with normal breaking. Can't lock them up on pavement, but just about can. I can get the tires to skip. Jeepforum has some great write ups on it. Don't think about doing it...just do it. You'll be glad you did.

http://www.madxj.com/MADXJ/technical...terUpgrade.htm

http://www.4x4wire.com/jeep/tech/bra...kes03/booster/

http://www.cardomain.com/ride/325707/15

[XJ_ranger]

Originally Posted by Sierra Drifter

Real World Measurements: + or - 1 or 2 thousands

I just pulled my master cylinder.
2001 Cherokee Sport stock master cylinder 1 inch bore.

Anyone know if all XJ cherokee MC's are 1" Bore?

Kragen lists the non-abs MC's for a '92 as 15/16" Bore...

[flexy92xj]

Swapped in a '00 WJ booster and M/C... works great but I did need a adj prop valve after taking out the stock prop valve.

Pics: http://rides.webshots.com/album/561412237cWcOoT

[Okie Terry]

Model-'92/XJ
Booster-'92/XJ
M/C-'97/Expedition 1.25"
P/V-'93 s-15
Front brakes-'03 SuperDuty
Rear brakes-'03 SD
Stops well on 39.5"s.



The previous MC had a wider mounting surface and a larger bore in the booster itself, which I remedied with a blockoff plate and smaller hole.
I also had to lengthen the push rod on the new MC and slot the mounting holes to fit the booster's studs.
Sealed it with RTV.



'92XJ, '97 Expedition




'92XJ, '97 Expedition



'92XJ booster



Used a sleeve and a short length of solid



Welded it to the MC







'93 s-15 PV

[Echo4charlie]

Does anyone have 78 Ford fronts and 78 Chevy 3/4 rear disks with brake setup that can actually say it works well? There is a lot of information in all of the brake threads but I still cant find one that says "this is what works and it works well"

[pipehitter155]

yeah i have them in my 99 and everything is stock as far as the braking system goes...i have a rear 14 bolt w/ 78 K20 front D44 calipers, discs, pads, etc. and a front 78-79 HP60 w/ dual piston caliper and it stops on a dime...no problems...guess i just got lucky...

[lookin4fun_inca]

Originally Posted by Echo4charlie

Does anyone have 78 Ford fronts and 78 Chevy 3/4 rear disks with brake setup that can actually say it works well? There is a lot of information in all of the brake threads but I still cant find one that says "this is what works and it works well"

I got hte 14bolt rear with the disc conv. w the 44 calp. and the front is a rockjock with the stock D60 1979 dual piston 3/4t calipers and rotors

I have the 04 WJ booster and master, no prop valve and all stock lines expect extended at the ends. Stops my 3000lbs buggified XJ on 40's very nicely!

[Echo4charlie]

Originally Posted by pipehitter155

yeah i have them in my 99 and everything is stock as far as the braking system goes...i have a rear 14 bolt w/ 78 K20 front D44 calipers, discs, pads, etc. and a front 78-79 HP60 w/ dual piston caliper and it stops on a dime...no problems...guess i just got lucky...

My pedal goes to the floor. My MC is a 1991 XJ, so single booster. I think I am going to try the WJ setup. Thanks you lucky bastard

[pipehitter155]

shit i gotta WJ too (it's the ole lady's ride)....that thing can't wait to stop...man i bet that is your best bet honestly (going with a WJ setup)...

[Bubba_Jeep]

Originally Posted by vetteboy79

There are hundreds of threads on this topic, but they all contain a huge amount of hearsay and uninformed responses, and the true tech gets buried.

I'd like to have a thread in which only people who have actually SUCCESSFULLY completed a master cylinder upgrade should post the following:

- Year/model of vehicle
- Year/model/style of booster
- Year/model/style of master cylinder
- year/model of proportioning valve (if used)
- Front brake configuration
- Rear brake configuration
- Overall performance

What we DON'T need is a bunch of people saying "I've heard you just swap in a E350 master cylinder" or "A 79 corvette MC works".

Sorry if this is a repeat, but I know I've been quite frustrated trying to find any accurate information on this, and I know there's some others out there with the same problems.

PLEASE, ADHERE TO THE ABOVE PURPOSE OF THIS THREAD! THE IDEA IS TO HAVE POSTS THAT SAY: "I'VE DONE IT CORRECTLY , MEANING WHAT i DID ACTUALLY WORKED.
The point here is to get feed back and detail about what really works, and the part numbers/mods/adjustments required to make it work.

[JayH]

- Year/model of vehicle
- Year/model/style of booster
- Year/model/style of master cylinder
- year/model of proportioning valve (if used)
- Front brake configuration
- Rear brake configuration
- Overall performance

1995 ZJ

1991 XJ

1988 E350

none

Mid - late 80's 3/4 ton calipers on CJ rotors on 609

1979 Lincoln Calipers on Ford 9

Sweeet

[dhoffryn]

- Year/model of vehicle
91 XJ w/abs

- Year/model/style of booster
2000 WJ

- Year/model/style of master cylinder
2000 WJ

- year/model of proportioning valve (if used)
98 TJ with the o-ring removed

- Front brake configuration
D30

- Rear brake configuration
Exploder 8.8

- Overall performance
Really soft peddel ... feels like there's air in there, but have bled it 3 times already. Can lock up 35s on dry pavement now though. ABS finally tossed.

[troy6187]

88 mj

95 xj booster

95 xj master

stock prop valve with stock load sensing valve in rear wired for full pressure

98 xj front brakes

98 exploder rear discs

stops excellent with 35s... solid pedal and great feel. dont know if i can lock up the tires on pavement as i havent tried.

[wheatfield]

91 XJ

91XJ booster

78 Merc Marque 4 wheel disk hydroboost cylinder

Willwood Adj prop valve full open (could be taken out)

77 Chevy 3/4 ton rotors and calipers front and rear

works well (much better than the Vette cyl I used to run)

Scott

[CrawfishStu]

Originally Posted by vetteboy79

- 94 XJ
- 95 ZJ dual-diaphragm booster
- 1998 Dodge 2500 MC
- 95 ZJ distribution block (ABS removed)
- Large single-piston D60 calipers (front)
- GM 1/2-ton calipers (rear)

Much better than the stock MC on the same setup.

The Dodge MC bolts directly in place and seals properly; you need to extend the pushrod by about 5/8". I made a spacer to go in the pushrod bore of the MC. It's still a little too short but I haven't had the motivation to take it apart again.

The flare fittings are the same as the stock XJ so no cutting/reflaring is necessary.

Left to right:



'95 ZJ, '98 Dodge 2500, '94 Dodge 2500. I ordered the wrong Dodge one initially.



I forgot all about this thread.

When he talks about cutting a 5/8 spacer, what exactly does that mean? Something 5/8" long to drop in the bore?

[Moore87]

Originally Posted by CrawfishStu

When he talks about cutting a 5/8 spacer, what exactly does that mean? Something 5/8" long to drop in the bore?

Yes but the most common way to do it is to remove the pushrod from the pedal and swap it with a bolt that is longer. Then round the head on the bolt to match the end of the pushrod. Here is a great thread for it

http://pirate4x4.com/forum/showthrea...aster+cylinder

[hammerdownxj]

1995 xj 2dr se
axles: d44 3/4 ton front 14b ff rear
brakes" discs front and rear
proportioning valve: willwood adjustable
master cylinder: 1978 chevy 1 ton

This things stops amazing. I couldnt be happier with how the brakes work. None of my friends rigs can stop as good as mine can my setup works the best.

[Echo4charlie]

What mods did you have to do to the Chevy MC?

[hammerdownxj]

open up the 2 holes on the mc to attach it to the jeep booster that was it.