Written By: Mike Ruta

Edited by: Sean Putman

The factory 9″ drum brakes that came on our beloved early Jeeps leave a lot to be desired. Stopping power is not one of their greatest attributes. Luckily enough, there is an easy way to improve the braking of the early Jeep. This method is known as the 11″ drum brake swap and is probably the oldest and simplest way to improve braking on early Jeeps. Depending on how and where you get your parts, it can be very cheap as well.

Please note that this modification can be performed almost identically on any 1945-1971 Jeep CJ. Therefore, although the title is early CJ5 11″ drum swap, this applies to all CJ’s falling between these model years. Please also remember that even though this modification should greatly improve the braking performance of your Jeep, if done incorrectly, the results can be harmful to you and your Jeep’s health. While it is a simple modification, a minor mistake with brake work can cause complete brake failure. Even the least technical person can understand that. With all that being said,let’s get started!

Probably the simplest way to get the parts needed to complete the swap is to remove all front axle brake components (drum to backing plates) off of a 1972-1976 Jeep CJ. I say to use the front axle part because if your braking system is the factory setup, you will want to swap your front brakes out for the bigger ones since the front brakes do the majority of the work. Parts from other vehicles can be used as well. Just make sure that no one is using that vehicle (duh). If you have successfully used parts from another vehicle, please let me know so one day it may be added to this article. I got my parts from a 1974 CJ5 that I parted out. I decided to rebuild or replace all components except for the backing plates. All parts I purchased came from either NAPA or AutoZone. A breakdown of the parts needed (for the 1972-76 CJ) is as follows:

Please note that there may be other part numbers available for the application. The above part numbers reference the cheapest parts available at the time this was written.

The first step is to lift your Jeep and safely support it with jack stands so you can remove the wheel from the side you decided to start on. Next, remove the drum (and lockout hub from the spindle,if so equipped). Lockout hubs come in many different designs but usually you need to remove some kind of cover piece held in with bolts or Allen screws, followed by a snap ring. The pictures below show the lockouts found on my front axle.

Front axle lockouts

The next step is to remove the wheel hub. Once the lockout is removed, a large nut on the end of the spindle becomes visible. It can be removed with a large socket available from most 4WD parts vendors or through careful positioning of a screwdriver between a flat side of the nut and the wheel hub. Okay, I lied. You’ll have to jam the screwdriver or chisel in there and then turn the wheel hub counterclockwise. This way might take a little practice. The wheel hub nut is visible here:

Wheel hub nut

After the hub nut has been removed, you should find a washer separating it from another identical one. The washer can be removed by hand and the second nut probably can as well. With the hub nuts out of the way, you can pull the wheel hub off of the spindle. At this point, your progress should look something like what you see below.

Wheel hub pulled off spindle

Hopefully you don’t find your brakes as nasty looking as mine. Once you are at this point, you’ve almost completed the teardown process. The only thing left is remove the spindle and backing plate. You must remove the six bolts (hidden under the crud in the picture) around the center of the backing plate to get the backing plate and spindle off. You also have a choice to make here. The backing plate won’t get very far if you don’t disconnect the flexible brake hose from the wheel cylinder. You can either remove the hose from the wheel cylinder or from the rigid steel brake line at the frame. Or you can do what I did and cut the rubber line. Throw the old stuff in the trash or put it in your “for sale” bin, then pull the spindle off. At this point, you should be looking at something like the picture below.

Bare knuckle and axle shaft

If you’ve got it down this far, now would be the perfect time to do your kingpin bearings and replace your leaky knuckle seal as well. That’s what I was doing here (this may be covered sometime in the future). I won’t take any more time explaining the installation process since it is the exact opposite of pulling it apart. I think I will let the pictures do the talking. Please let me know if you find any errors or content which you think should be added here. The contributors of the Early CJ5 Page are as much responsible for writing this article as I am since it provided me with the information I needed for the swap. Good luck and happy Jeepin!

Putting it all together:

Completed Assembly

Bronco brake swap information

From Ron Sherry

I have a 68 CJ-5 I converted from 9″ to 11″ brakes by using older Ford Bronco Brakes. The backing plates bolt right up with no modification needed and the drums do the same on the rear but I had to remove about 1/4″ of metal from the fronts to slide over the hub. I got all four backing plates with shoes and drums on Ebay for under $100.

I purchased everything on Ebay by searching “Ford Brakes” or “Bronco Brakes” or “Jeep brakes” and them just read through what came up. Some times it takes a week or two before and item you need shows up, but if your patient it will show up. I purchased one complete set of drums, shoes and backing plates for $20, and because I lived within 100 miles of the seller I picked them up instead of shipping them. The other set I paid about $30 for and another $20 to have them shipped to me. I didn’t have to worry about whether or not they were fronts or rears because my parking brake was on the rear of my transfer case, (which I got rid of and now us a Mico lock), so I threw away all the parking brake linkage. I think a lot of the early 70’s broncos had the six bolt backing plates and 11″ x 2″ brakes, so any wrecking yard with older Fords would probably have them. This year I tore out the mechanical pedals and installed hydraulic swing pedals out of a Mazda so now my 11″ brakes are power assisted and my clutch no longer binds when I rock crawl. What a great change.

Thanks for that tip Ron

Editor’s note: I don’t recommend using a Mico lock as your parking brake. If you break a brake line you don’t have any brakes using Mico locks. Mechanical parking brakes are still a very necessary thing on any trail rig IMO.

Additional Information from Thad Robosson

Added 19 Feb. 2006

Buying new parts for the 11″ brake conversion

By Thad Robosson

When getting parts gathered to do an 11″ conversion, there are two ways to do it. The first way is to go scrounging in the junkyards and coming up with a (hopefully) complete set of drums, backing plates, and hardware for your project. The second way is to do a little shopping for new parts. After doing some research, I have obtained everything but the backing plates brand new.

In the article by Mike Ruta (above), there is a list of part numbers for the items you’d likely be replacing if you were to go the junkyard route. I have found that there are other part numbers available that will lessen the likely hood of you getting your hands greasy prior to actually working on your Jeep. Your experience may be different than mine, but this should get you in the ballpark. All the part numbers I listed below for new hardware was found by being nice to the counter people at my FLAPS (when they weren’t slammed with customers) or by making a phone call or two.

First off, the part numbers in Mike’s article are all usable, but there are some notes….

• The Autozone number of 882 for the drums should be 8882, at least it was at the store I visited. I do not know if the drum for this number was finned or not.
• The NAPA part number UBP 80409 is for the holding pins, springs, and retaining washers only. It does NOT include the shoe-to-shoe springs nor any self adjusting hardware.
• The NAPA part number UBP 6401259 is for the finned drums. This is only an issue if you plan on doing the drilled drum modification, or simply don’t want the fins.

Secondly, here are the part numbers I used for new hardware…..

• Drums…non-finned, Omix-Ada part number of 994305 (old #) OR 16701.04 (new #) (Most online places like Krage or Walck’s will carry Omix-Ada.)
• Shoes…NAPA part #RBP AE10AR, same as Mike recommended. 1 per axle needed.
• Wheel cylinders…NAPA part #TSW 4636017 and #TSW 4636018, same as Mike recommended.
• Hardware kit…Checker Auto part #507137 (Combination Kit). This is all shoe-to-backing plate retaining hardware and shoe-to-shoe springs. 1 per axle needed. This is a Raymold part #, so you may find this number used at other parts stores.
• Self Adjusting kit…Checker Auto part #H2540 and #H2541. This is all the self adjusting hardware. 1 per wheel needed. THESE ARE LEFT OR RIGHT SPECIFIC! These are Raybestos part numbers that you may find used by other parts stores.
• Wheel cylinder links…Omix-Ada part #48331. This is slotted pin that goes from the wheel cylinder to the brake shoe. The slot on the end fits onto the brake shoe. 2 per wheel needed.
• Brake shoe retaining washer…Omix-Ada part #3201023. This is the diamond shaped washer that traps the brake shoes at the upper pin on the backing plate. 2 per axle needed.

So there you have it. No real surprises here, and I was able to pick up all the new parts locally. Only thing to get greasy for is the backing plates!

Elsewhere on the web see:

11″ Brake Swap tips on the CJ-3B Page

Drum brake servicing on Dippy.com