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

[vetteboy79]

THIS THREAD WILL BE MODERATED:
This thread is for reporting specific combinations you have tried.
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.

[Bubba_Jeep]

Ok, I think this would be a great thread if only actual experience is reported here.
I'll start with the current system on my '88 XJ Laredo:
'88 XJ Laredo
'78 Mercury Marquis with 4-wheel discs and hydroboost
http://napaonline.com/masterpages/NO...linder+-+Remfd

'88 XJ combination valve; gutted
'76 Chevy single piston, 1/2-ton calipers in front
'80 Cadillac Eldorado (metric) calipers in rear
Braking is good, much better than stock; however, I plan to upgrade to dual booster as soon as the correct MC is identified

[87manche]

Originally Posted by Bubba_Jeep

Ok, I think this would be a great thread if only actual experience is reported here.
I'll start with the current system on my '88 XJ Laredo:
'88 XJ Laredo
'78 Mercury Marquis with 4-wheel discs and hydroboost
http://napaonline.com/masterpages/NO...linder+-+Remfd

'88 XJ combination valve; gutted
'76 Chevy single piston, 1/2-ton calipers in front
'80 Cadillac Eldorado (metric) calipers in rear
Braking is good, much better than stock; however, I plan to upgrade to dual booster as soon as the correct MC is identified

hydroboost is cool, got any pics?

good topic... free bump

hey man, the thread is about what master you can swap into yer rig, not brakes per se. this bolted up and works great. yup, the pedal is hard, it reacts quickly. it works good, and the rig is ready for the big calipers that come with big axles. this is good info if a fella is building incrementaly, as most are. i tried to follow the guidelines set in the first post. all my info is there.

Tech to the top BS to the bottom...

I have a Ram 1500 master laying around that might also be a good swap. I will get some measurements and post up some pics in a day or two.

Originally Posted by TJP

I have a Ram 1500 master laying around that might also be a good swap. I will get some measurements and post up some pics in a day or two.

There is no speculation allowed in this thread.

Originally Posted by vetteboy79

There is no speculation allowed in this thread.

I'm fully aware that there is no speculation allowed, but posted that because I would check fitment so no one else buys one try since I have the master already.

If it's a no go I will edit my post so no one else trys one...



clean up

It's been more than a day or two.

Originally Posted by vetteboy79

I forgot all about this thread.

helped me out a good bit, so I decided to revive it

subscribing...

Thank you for the straight answer. I will give it a shot.

reblead the brakes for the time being and see what happens. When we got that going I never got all the air out of the lines.

What about if your not doing rear disks on a d60? Im swapping in a d44/d60 from a 78 F-250, with calipers and keeping the drums in the back. What would the e350 M/c feel like, and or do I need any additional mods, such as o-ring removal, etc?

Originally Posted by jayh

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

holy shit the first one

OK, so a lot of these master cylinders being mentioned come from vehicles with drum brakes in the rear, but are being used w/ rear disc conversions. The vehicle they come from may have had a rear disc option, but I'm not seeing a distinction in the parts listings on RockAuto.com (I've checked the Durango, E-350, Corvette, 2500, K30, etc).

Apparently volume isn't an issue to the rear discs? And these MC's must not have a built in residual valve for rear drums?

My assumption is that the manufacturers are using the same MC for either rear brake system, giving the rear reservoir enough volume for either setup, and putting the residual valve in the combination/proportioning valve? Does that make sense?

Thanks,
Billy

I have the Ford 2 piston calipers found on their older D44/D60 in the front and the Chevrolet 3/4 ton single piston calipers on the rear. I used the 77/78 grand marquis master, wilwood prop valve, stock 92 booster. The rear will lock down with ease even with the prop valve turned all the way down, but the front breaks are lacking. I am wondering if it is from the diameter of the stock break lines not allowing enough fluid to move the massive ford dual pistons. I have bled and bled the front and no change. I cant really trouble shoot right now because the front axle is removed for some freshening up. Just thought I would see if I could get some ideas from the masses to help when I button it back up. I do have brand new calipers coming. Does anyone think I should go with a larger diameter break line, or does that not have much effect?

What if I used the master cylinder from a '79 F250? Has anyone tried, or know the specs?

has anyone played around with not running any sort of booster?

Originally Posted by Weasel

has anyone played around with not running any sort of booster?

You'd want to run a manual ( NON power ) M/C to do it right.

With fear of flamage, I did a manual Disc swap on my '72 Nova, used a '69 Camaro manual disc M/C, '76 Malibu prop valve, '73 Nova discs, calipers, spindles.

You'd have to find a M/C that was manual disc/drum, or disc/disc depending on your set up. A "power brake" M/C would give you a VERY hard pedal if you tried to run it without a booster.

Top of my head, Camaro, Corvette, Chevelle, Mustang, Charger, Valiant, Volare, would be some to look into for bore size/hole spacing match ups....

I was thinking Wilwood..

Originally Posted by Weasel

I was thinking Wilwood..

Sure.....do it the easy way.....









Ok
91 Xj
93 D60 calipers
K20 calipers on 14 B
90 E350 MC
Wilwood Valve
Stock prop
37" tires

The rear works great and not enough front brake pressure. Should I bypass the stock Prop valve?

Originally Posted by crzyxj

Ok
91 Xj
93 D60 calipers
K20 calipers on 14 B
90 E350 MC
Wilwood Valve
Stock prop
37" tires

The rear works great and not enough front brake pressure. Should I bypass the stock Prop valve?

From original poster as to the purpose of this thread:

"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:-----"

Sorry Bubba.....

Come on, guys. This thread was intended to be testimonies of after the fact SUCCESSFUL upgrades to MC's and associated systems--not a discussion forum for "what ifs", and "why won't this, or that work".
There Are many, many threads on Pirate regarding problems encountered with various systems, filled with ideas, but with few operational solutions. This thread was suppose to be a collection of verifiable, successful installations.

I have a 78 CJ7 with out power brakes, the master cylinder shot craps so I scored a working 90 XJ MC and Booster for free. I had to make a bracket to mount it and hold it out 3/4" It works great, locks up the 34" LTB's but I'm not satisfied with the pedal feel, it is way soft. I have blead and blead the brakes but it doesn't help. As soon as I start appling the brakes they engage and slow you down apply more foot and they stop, basicaly everythng works good except for pedal feel. I'm running disc on front and drum on rear,stock, and a new CJ p-valve. Does anyone have a suggestion ?

90XJ Booster
90XJ MC
CJ D30 Stock Front Calipers
CJ AMC2o Stock Drums
CJ New P-valve

I have a XJ 91 with stock brakes and I find this very usefull, but have any of you guys put in an aluminium caliper front and rear?

[lookin4fun_inca]

ok real world measurements. I think stuff like this is critical to true tech also.

Durango/dakota - A1C132967 part number said to be 1999-2001
Would say its 1.900 OD (caliper loosen some when I let go.


Stock WJ (dont know what yr to yr but do know it was out of a 04) 1.730 OD


As you can see the durango/dakota will not fit/seal the WJ booster. I also measured the CL hole spacing and it was the same as the Durango. I can not verify though the OD of the booster mount bore, as I returned it to fast and forgot.

CAN someone please take measurements from the follow if they have (pict would be nice to).
single XJ booster (pre 95) bolt mount spacing and OD of mount flange/bore
Dual XJ booster (95ish newer)bolt mount spacing and OD of mount flange/bore
and any and all attemped MC or booster related to a XJ swaps (any and all diam)

[Sierra Drifter]

Originally Posted by lookin4fun_inca

ok real world measurements.

I think gathering real world measurements is a fine idea however I think we need to be consistent and clear how it is done.

You said: "Durango/dakota" What year? What part number?

Pictures of calipers are ok, but rather than relying on everyone interpreting the picture of the caliper, how about we just say, in numbers, what the measurement is. The glare on the caliper in second picture is so bad my old eyes can't even read the numbers.

Could we do something like:

1999-2001 Dakota/Durango MC
Napa (or DC, or whatever) Part Number: xxxxxxx-xxx
Diameter of MC where it enters the booster: x.xx inch or xx mm
Length of MC where it enter the booster: x.xx inch or xx mm
Distance hole-to-hole mounting flange: x.xx inch or xx mm
Diameter of mounting flange bolt holes: x.xx inch or xx mm
And then include a couple pics.

Are there any other relevent measurements that should be recorded?
What do you guys think?

Also in the first pic, it appears the caliper isn't touching anything on the left side.

Lastly. I can provide measurements from a stock 2001 XJ, when I get home.

[lookin4fun_inca]

Originally Posted by Sierra Drifter

You said: "Durango/dakota" What year? What part number?

Pictures of calipers are ok, but rather than relying on everyone interpreting the picture of the caliper, how about we just say, in numbers, what the measurement is. The glare on the caliper in second picture is so bad my old eyes can't even read the numbers.

Also in the first pic, it appears the caliper isn't touching anything on the left side.

Editted. See numbers. And yeah those must be some old eyes

those of a 2001 would be nice.

[Bubba_Jeep]

87Manche, I don't have hydro boost. The MC is from a Mercury with hydro boost.

Lookin4fun, that's useful input, thanks.

[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.
Not sure about DC part number.
Cast on the bottom of the MC: BENDIX 0180C 4028 34
Cast on mounting flange: F102 0223
Cast on the end of the MC: 0236C 4651

Diameter of MC where it enters the booster: 1.75 inch
Note: the cylindrical part of the mc that enters the booster steps up to a larger diameter just before the rubber seal. This is the part that actually seals against the booster. The diameter at this point is: 1 29/32 or 1.9 inch

Distance hole-to-hole mounting flange: 3.21 inch

Diameter of mounting flange bolt holes: 11/32 inch

[olivedrabxj]

heres my brake set up for your viewing pleasure

87 xj
master/booster-99wj
prop valve-stock 87 xj with o ring removed as outlined here- http://www.4x4wire.com/jeep/tech/bra...alve/index.htm
front brakes-99 wj knuckles/calipers/rotors re drilled to 5x4.5
rear brakes-00 explorer 8.8 disks.

the jeep stops awsome on 35s i can lock up all 4 at will even brakes straight.

i orignally set out to use the wj knuckles for the crossover steering but the brakes were the best part of the swap it stops 1000 times better than it did with the orignal brakes

justin

[Caper]

'93 ZJ/xj d44 rear.

front brakes stock. no abs, ripped it all out.

rear disc setup: 95 ZJ front rotors (hub center fits over d44 axle center) with '88 YJ calipers with the bolt on mount bracket. factory caliper bracket bolts to bracket welded to axle.

master cylinder: '85 E350, with holes ground out a bit to fit over booster studs

booster: '88ish XJ. it is bigger than other XJ ones i have looked at, maybe it is dual diapham? i never confirmed that.

no prop. valve - should be using one on street, nice on the trail tho. 50/50 distribution.

biggest problem i had was adjusting the little screw guy between the booster and the brake pedal. needed to back it off 1/8" it is super touchy to adjust, use very small increments. 1/4 turn makes a difference.

been running 2 years no problem.

summary: ZJ with E350/XJ booster bolts up.

[vetteboy79]

So you've got an E350 master with stock brakes...

That has to be a hell of a stiff pedal.

[kirbyiv]

im running the stock '02 TJ MC with ford dual pistons in the front and chevy 3/4 ton fronts in the rear and the brakes work better than ever.

[Caper]

Originally Posted by vetteboy79

So you've got an E350 master with stock brakes...

That has to be a hell of a stiff pedal.

works for me and where my rig is at. it shows that we are able to do a master swap in an incremental build. the ZJ is ready for bigger brakes now, one less thing to do when the axles come.

anyway, offtopic....this is a good thread.

[MilspecXJ]

94 XJ
95 XJ Dual Diaphram Booster PN# 52008647
96 ZJ Master Cylinder 4 wheel disc
96 ZJ 4wdisc Proportioning valve internals ...all of it not just spring
94 XJ front stock brake configuration
87 XJ D44 w/ TSM disc kit using 79 Monte Carlo front calipers

I'm having an issue with inner pads not making a flush contact with rotor (till they wear in) on the rear TSM setup.

Jeep slows level, no nosediving. Braking is good, but i'd like to swap rear configuration to give me parking/emergency brakes.

[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.

[Sierra Drifter]

Well, my plans have changed. I was convinced that since I was running the large dual piston Ford calipers that I needed a 1.25 inch bore master cylinder to push a higher volume of fluid to the big calipers. However, after talking to a couple others with these calipers and after reading a great brake article, I realized that I was wrong. The dual piston calipers do not require the volume of fluid that I thought they did.

I highly recommend this article about disc brake systems. It is written by a guy who builds hot rods and race cars but the braking principals apply to any vehicle. He covers everything from the brake pedal to the rotors, as a system.

http://www.hotrodheaven.com/tech/bra...kes1_index.htm

I'm running an axle and brakes from a 1979 F250. That truck came stock with a 1 1/16 inch bore master cylinder, and it did not have a dual diaphragm booster. As such the 01 XJ with a 1 inch bore and dual diaphragm booster, is probably sufficient. Ideally I would locate a 1 1/16 or 1 1/8 inch bore MC, such as a the 99 Dakota/Durango. If I figure out the resevior/hood clearance issue, I will give it a try. Otherwise, I'll stick with the original 01 XJ MC. My front D44 is done, when the D60 rear is finished I'll be able to post my 'real world' results.

[shadowgamesxj]

1989 xj
- stock 89 booster
- 80's E350
- stock prop with missing spring/oring
- 1/2t chevy, on a HP44
- 1/2t chevy, on a ford 9
- overall it stops, locks the front up fine, the rear just slow, gonna do another bleed, with the calipers off the brackets, to see if I still have air trapped.

[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

[TJP]

Originally Posted by vetteboy79

It's been more than a day or two.

I did you one better and tested it.

I tryed a '98 Ram 1500 master on my 95 and it will not work correctly.

so rule that one out as a viable swap.

[heepr]

94 ZJ buggy
88 XJ booster
88 XJ MC
No prop. valve
Waggy D44 with stock waggy discs/ calipers
Ford 8.8 with stock Ford discs/ calipers
37" tires
Medium soft to lightly firm pedal. It's not like stomping on a cinder block, but it's no pillow either.

I ran the stock ZJ booster and MC for a while and it really did great stopping 37s. I removed it to ditch the ABS pump and lines, and install an electric line lock under the hood. First, I tried an '88 E350 master cylinder with an 88 XJ booster. After a lot of fooling around and wasted time I found out that they won't seal together properly.

Next I moved on to the '86 E350 MC that a lot of people are using. Its volume was too large for my relatively small calipers. I had a gorilla pedal that was firm even with a ton of air in the lines. The brakes performed really poorly, regardless of the pushrod length. Too far out, they would drag, and shortened to where they wouldn't only left me with minimal mechanical advantage over my calipers.

Then I grabbed an 88 XJ MC and bolted it to the 88 XJ booster. A quick pushrod length adjustment and the brakes are great. The rears will lock up awesome but the fronts don't like to as much. I can stop pretty easily on extremely steep grades, and I like the fact that I am not as dependent on the booster for braking power in case of the motor cutting off, etc.

When I move to one ton axles, I will switch back to the E350 MC. For now it is a great spare to have in the toolbox in camp. A buddy runs the E350 on his ZJ buggy with the 3/4 ton calipers on his 44 and calipers on his 14bolt also and it has a firm pedal and stops great due to the larger volume calipers.

[jpnbren]

Originally Posted by kirbyiv

im running the stock '02 TJ MC with ford dual pistons in the front and chevy 3/4 ton fronts in the rear and the brakes work better than ever.

Yeah I am runnig the same brake setup with all stock 93 cherokee mc and proportioning valve and abs unplugged it is a little squishy but no big complaints. i manly just said this to keep it to the top.

[Screwzer2]

'89 Jeep Cherokee 4.0L, D44 rear, D30 Front

Upgraded to Late model, larger brake booster and M/C

Notes:
1. To do this swap, you need to move the washer bottle. I used a radiator reservoir for a 4 banger, which tucks in between the airbox and the fender, picking up quite a bit of space under the hood. I used two outboard washer pumps which I mounted on a bracket I made and put in the shock tower pocket on the drivers side.
2. You WILL need the 1/8" thick aluminum spacer that goes behind the booster to the firewall to get the correct rod spacing
3. Its been a while since I did it, but I remeber having to dick around quite a bit with the pedal assembly, and I think ended up welding a bracket on a '96 pedal so I could mount the old switches. I'd have to go back and check my photos to be sure.

RESULTS: Greatly increased braking, no doubt due in great measure to the larger brakes on the D44. Was able to get a really clean install and I think I only had to make two lines. I'm running 33x12s and they stop on a dime. Very happy with the results.

If intersted, I can dig thru the other computer for photos....

[Bubba_Jeep]

Not only would the pictures be great, but how about sharing specific components used? Such as MC? Booster?
Include any part numbers and dimensions you took.

[TheRamChargerMan]

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

I just did this on my 88 XJ. I DID NOT have to move the washer bottle or swap brake pedal assemblies.

I used the master cylinder, brake lines from MC to prop vlv & booster from a 2000 grand cherokee with abs. I also used the 1/4" thick spacer (not 1/8" as someone else said) from a 95 XJ to lower my pedal height some. The spacer is not required, but it does make the fitment under the hood easier (less metal manipluation)

I retained my 88 prop valve, but modifed the 2000 lines to fit (cut metric bubble flare ends off and reflared using 88 fittings and a double flare). All the old brake switches still work as the factory intended them with very little needing to be done to keep them functional (the stock brake light switch is a POS design by the way).

My front brakes are stock 88 discs, and the rear brakes are stock 88 drums.

While I can't lock them up completely, they come very close. The jeep will try to stand on it's nose for ya now and before, it just blew it's nose at ya. This may be a result of not being able to bench bleed the MC due to the routing of the brakes lines, and I probably need to adjust the rear brakes again, as they were doing most of the braking before this swap.

I easily doubled my braking power, and for the 75 bucks worth of parts (booster/mc/lines & brake fluid), it was definitely a good deal and well worth the effort.


If anyone wants to tackle this, get hold of cal on NAXJA. He was a ton of help to me with getting the parts and explaining the in's & out's of what to do. The link posted above regarding the oring removal also was a big help.

If you have all the parts in hand, a double flare tool, and someone to help bleed the brakes, you can easily do this job in 3-4 hrs.

[Oatmeal]

Okay, I'll play. '96 XJ, stock m/c and booster stock discs/calipers up front, D44 with adapted Explorer 8.8 discs in back and ZJ proportioning valve internals......stops great and will lock em up easily--------Hans