Every $100 Spent, Earns $10 in Bonus Bucks. Enter FATHER

FREE SHIPPING on all orders $98+ See Details

Select Your Currency
  • Africa
  • Americas
  • Asia
  • Europe
  • Oceania
Shop Kaiser Willys

Disc Brake Dual Reservoir Master Cylinder Kit
Fits 41-71 MB, GPW, CJ-2A, 3A, 3B, 5, M38, A1

Part # 376896

New Dual Reservoir Master Cylinder Conversion Kit for DISC BRAKES ONLY

Free Shipping on oversized item!!

This kit is an important safety upgrade from a single reservoir braking system.

The kit includes a dual reservoir master cylinder, mounting brackets, brake light and all required fasteners and instructions.

The proportioning valve has a brake light switch built in the top.

This master cylinder kit is intended to install to your Jeep withouth cutting or grinding. You will need a 3/8" drill bit, a double flare tool, or a buddy with a double flare tool to modify your existing brake lines. You will retain your factory original master cylinder bracket. Its as simple as it gets!!!



Helpful Guides and Illustrations:
Dual Reservoir Conversion Kit - Install Guide
Propotioning Valve - Install Instructions
Master Cylinder Proper Bleeding Procedure

41-45 MB
41-45 GPW
46-49 CJ-2A
49-53 CJ-3A
53-64 CJ-3B
55-66 CJ-5
50-52 M38
52-66 M38A1

Please allow 2-3 weeks for delivery.

Part # Price





1 Item has been added to your cart!

Product Videos

Questions & Answers

Please Wait...

Ask Question Add Answer

All questions will be displayed after moderation. All answers will be displayed after moderation.

This master cylinder requires adapters to step down the brake line fittings to 3/16. This creates a clearance issue between the rear hole for the brake line and the bell housing. Any ideas on how to create the proper bend for this to work? I think without the adapter it may work but the fitting adapter takes up precious space for the brake line.

Willys Jeep Parts Tech:
Please either give us a call or email mike@kaiserwillys.com and we can assist you.

what is the bore size of this m/c ? Im looking for a 3/4 inch bore m/c for a disc/disc conversion. Thanks.

Willys Jeep Parts Tech:
I believe 1" but email mike@kaiserwillys.com so we can get more vehicle information and help you. They are correct for what we list.

Is the master cylinder an over the counter part for eventual rebuild or replacement? I don't want to build my Jeep with non standard parts.

Willys Jeep Parts Tech:
If you get this, you can always give us a call if you need parts and pieces.

Will this clear a ramsey front PTO for winch

Willys Jeep Parts Tech:
It might be tight depending how the ramsey driveshaft comes out.

Purchased Part # 376896, wondering why there is no rubber boot with this? You would think for $400 it should come with it, the dirt & road grime would agree.

Willys Jeep Parts Tech:
Give us a call and ask for Mike M

I am upgrading the front brakes on my 1962 CJ3b to front disks and am leaving the rear stock drums. I would like to use your kit 376896. In the future I would like to add disk brakes to the rear. When I do this would I have to purchase another master cylinder when upgrading the rear to disks or would the master cylinder in this kit be OK as is?

Willys Jeep Parts Tech:
Our kit will work for both disc / drum set ups and disc / disc set up since its a dual reservoir with a fully adjustable prop valve included.

Hi, Im looking to install the dual master cylinder upgrade to my '62 CJ5 and am eventually going to install front disc brakes (one thing at a time). Can I use part # 376896 and either adjust the proportioning valve accordingly or not use it until the disc upgrade is done? I realize I'll need to mount the brake light switch somewhere if I leave the proportioning valve out. I'm trying to avoid purchasing two different master cylinders, one now and one when I upgrade to front discs. Thanks.

Willys Jeep Parts Tech:
Yes, you can just line in the adjustable proportioning valve at a later date if not using the discs till then.

I have completed a disc brake conversion on my front brakes of my CJ2A. My back brakes are stock. Will the master cylinder kit 376896 work for my set-up?

Willys Jeep Parts Tech:
Yes, that is the part number you need.

Hi, is this the correct kit for a disc/drum brakes for a CJ3A?

Willys Jeep Parts Tech:
Yes, that is correct.

Does this kit include the proportioning valve?

Willys Jeep Parts Tech:
Its comes with a fully adjustable one.

Is it possible just to order the bracket and mounting hardware?

Willys Jeep Parts Tech:
Yes, we can get that set up for you. Just give us a call toll free and we can work a quote up for you. Thanks

Is the master cylinder available separately ?

Willys Jeep Parts Tech:
Email mike@kaiserwillys.com to help out.

Is this the only master cylinder that will work with front disc’s? I purchased a 1968 CJ 5 V6 from my friend who converted to front discs. The vehicle has the original style master cylinder #945556. A proportioning valve and check valve for rear brakes is in line.

Willys Jeep Parts Tech:
I would personally use this kit. But a dual res mastery cylinder with a prop valve would work if proportioned correct.

Can this master cylinder be used with my old drum brakes, until I convert them over to disc up front? That way I can convert them in stages.

Willys Jeep Parts Tech:
Yes, the prop valve would not really be necessary and you could just plumb it in later.

If I need to replace this master in the future can I buy it separately?

Willys Jeep Parts Tech:
Yes, that is not a problem.

Dear Gents about a year ago I bought this kit item # 376896 for a Jeep I am reparing but the project got delayed, today I find out that I have the pump but somebody misplaced all the hardware. Question: Do you sell the hardware without the pump?

Willys Jeep Parts Tech:
Please email mike@kaiserwillys.com to help.

Where do you mount the proportioning valve?

Willys Jeep Parts Tech:
Anywhere out of the way. Typically on the frame rail just forward of the master cylinder.

Can you guys clarify if I need to cut off my Stock frame master cylinder mounting bracket? It says in the product description above on this page that no cutting is required but the first step in the directions says to cut it off. I have a 1966 CJ5 V6. Doing a dry fit up it looks like it needs to come off to give this new master cylinder enough room to sit square in front of the new bracket. Thanks.

Willys Jeep Parts Tech:
That is for the very early Willys. Please email mike@kaiserwillys.com and we can help out on any questions.

I ordered and installed Brake Conversion kit/SKU 376895. Works well. You descrive SKU 376896 as the Master Cylinder for this Kit. However, I have a Jeepster Commando/1967/V6/4WD and that isn't shown on your site as compatible. Will the SKU 376896 match up to 376895?? Thx

Willys Jeep Parts Tech:
We dont have a dual reservoir kit for the C101. The master cylinder and prop valve in the kit will work but I dont have a bracket system to mount up the the C101 frame area.

Any recommendations or the best place for the proportioning valve on a CJ2A?

Willys Jeep Parts Tech:
It screws directly into the port on the front of your intake manifold. See our shop by diagram section.

Do I need residual valves in line or does the mc take care of it along with proportioning valve?

Willys Jeep Parts Tech:
See the link above in the description on the prop valve hook up.

I've installed completely new axle assemblies with late model GM truck disc brakes both front and rear. Will this work for me?

Willys Jeep Parts Tech:
No, this is for Disc / Drum set up. But we do have a kit for Disc / Disc set up. Please call and ask for Mike M.

Is your MC set up with a 2 lb. residual pressure valve or does it need to be added & purchased separately? Thanks

Willys Jeep Parts Tech:
It comes with a external prop. valve. Keep scrolling thru the photos, we have an image of it as well.

On the lid gasket/diaphragm does the flat side of the gasket face down (fluid side) or up (lid side)?

Willys Jeep Parts Tech:
It faces down. Thanks

What master cylinder should I use to convert my 1960 CJ5 to front and rear disc brakes, using your disc brake conversion kits?

Willys Jeep Parts Tech:
This is the one. Call in the order and we can put down you need it for Disc / Disc brakes for front and rear.

Is this glass cut to order?

Willys Jeep Parts Tech:
Yes, that is correct.

I have a 68 CJ5 with 10" drum brakes front and rear. I have the dual reservoir master cylinder (stock) now. I am adding later model CJ5 disc brake front axle. will this work or does my current master cylinder work by adding the disc/drum proportioning valve? I am not adding power booster.

Willys Jeep Parts Tech:
You may be able to add the prop valve with your current set up. The 376896 will work for you too. Email mike@kaiserwillys.com and i can try to help as well.


Willys Jeep Parts Tech:
805223-CJDUAL is for drum / drum brakes or we have a booster kit part number: 805200

I bought this kit and the plunger part is too long. Is there a shorter one? Or, do I need to cut it down? I screwed it all the way in and the body hits the brake pedal, but still needs to come forward about an inch or two.

Willys Jeep Parts Tech:
Please call us toll free - we can walk you thru the install. Your plunger is adjustable and we provide the proper parts.

We bought the disc brake kits for both front and rear of a 61 cj5. got master cyl and porporion valve. doe this need the porp valve with disc on both front and rear?

Willys Jeep Parts Tech:
Only one prop valve is required. We sell different versions depending if your Disc/Drum or Disc/Disc set up.

I have a 46 CJ2a and want to convert front and back to disc. Item 376896 Dual reservoir master cylinder states only for front disc conversions only. Will this work with front and back disc conversion?? Mike

Willys Jeep Parts Tech:
If you order it together we can make it set up for Disc/Disc brakes. Please call us toll free. We are happy to help out with.

How does this Seat Cover/Cushion with Plywood Pan attach to your Seat Frame Item # A2286-2A? My rusted out "Old" seat frame had a metal pan attached to the frame via TWO 1/2" Bolts from the bottom that screwed into captured nuts in the pan and the back was held in place by TWO "L" Shaped "Clips. 1948 CJ2A S/N 180978.

Willys Jeep parts tech:
Our plywood pans come with the cage nuts for you to run thru the slats in the seat. Or the pans we offer will have the triangle corners for a drawstring set up.

does this kit come with the proportioning valve

Willys Jeep Parts Tech:
Yes, you can scroll thru the photos and see it as well and in install instructions.

I have a 1948 CJ 2A Willy's Jeep. I have upgraded to 11 in CJ 5 drum brakes in the front and have the stock 9 in drums in the back. I am using the stock single reservoir master cylinder ... having a little trouble stopping. Will your dual reservoir master cylinder help mean this area?? Thanks for your help.

Willys Tech:
Yes, you should be ok with your set up and those brakes you currently have on there.

Will this work if both front and rear axles are converted to disc brakes, or is it only for front disc with rear drum brakes?

Willys Tech:
This is for a Disc/Drum set up. We can do one at the same price for Disc/Disc set up. Call us toll free.

Does this fit the stock brake switch?

Willys Tech:
Yes you can, you just have to line it in when you make your brake lines.

Does this fit in stock location, where single piston cylinder is located?

Willys Tech:
Yes this fits on the drivers side frame by the brake pedal in the original position.
Request Catalog
THANK YOU! Your catalog request has been submitted successfully. Please note:

If your catalog does not arrive within 7-10 business days, call us Toll-Free at (888) 648-4923.

Email Subscription
THANK YOU! You have successfully subscribed to our newsletter.
Contact Form
THANK YOU! Your contact form request has been submitted successfully.
Photo Contest
SUCCESS! Your photo contest entry has been submitted!
Browser warning
The browser you are using to visit our website is no longer supported. For the best browsing experience, please visit us using a different browser.
I understand, close this message