Dedicated to the preservation of Chrysler, Plymouth, Dodge, and other Mopar automobiles from 1955 to 1973

Chrysler    Imperial     Dodge    Dodge Pickup    Desoto    Plymouth 


Moore Used Cars

USED Mopar Parts



Useful Links

The REAL Christine

Project Cars

Rust Buckets

Members Rides



New! Repro
 Chrysler Lenses


Disc Brake Conversions.
Give a lazy man a job to do and he will find the easiest way to do it.

Let's face it.  The brakes on the old cars were good for their time.  There was less traffic and our pace was slower.  But things have changed and our cars need some upgrades so we can enjoy them safely today!  Being the owner/driver of a few of these I thought a brake upgrade would be a good thing to do.  Especially if you don't want to have to crawl under your car 10 times a year and adjust the brakes. . . Not to mention finding some of the parts. . . . 

I've done those junk yard conversions in the past.  They are a nuisance, unless you like the challenge and have time on your hands, you'll have to go to several different cars or yards at times.  And you still have all used parts.  Ask yourself.  Is it worth it?  Or would you like to have it done in an afternoon with maybe a side trip to a good auto parts store?

The old drum brakes were prone to fade, hard to adjust, particularly the fronts so the car didn't pull.  Disc brakes are much more efficient, run cooler, and need no attention throughout the pad life. 

Let's look at a Disc Brake conversion for a 55 to 65 Chrysler Product.  By the way, a very similar kit is made for the Ford Econolines and soon, the small Ford Body cars.  (We're not supposed to say that word here.)  Those kits are provided by D & D Disc Brakes, in Philomath, OR

There are a couple of manufacturers out there that make kits for the old Mopars.  You have to evaluate what you want to do with the car, but the best bang for the buck in conversions is AAJ Brakes in Portland, OR.

I am going to show you a disc brake kit that is a direct bolt in.  There is no machining or welding to do,  you don't even have to remove the spindle.  The AAJ Kit will fit under your stock 14" wheels too!  Parts are easy to get as it uses a General Motors Caliper and a Mopar B Body rotor.

This operation is very simple.

Lift the car and support it with jack stands.  Remove the front wheels.  Remove the drums.  Disconnect the brake hose from the steel line.  Be careful not to twist the steel line.  I suggest you spray the fitting with PB Blaster first or another good penetrating oil.  If you are in doubt of the line or it is pretty rusty, prepare to replace it.  I also strongly you purchase or borrow a quality 3/8 line wrench.  "Cheap" tools don't cut it.  Remember these are life savers we are talking about.

There are 4 bolts holding on the backing plate to the spindle.  Remove them.  Clean up the area, spindle, make sure everything else is up to par before you proceed

When you buy the brackets from AAJ Brakes, you get 4 bolts with it.  Use 2 of those to mount the new  bracket.  The 2 longer bolts are used to remount the steering arm.  From experience, I found that occasionally the casting for the steering arm is oversized a few thousandths. If all the holes don't line up immediately, then you may have to file a bit off the steering arm.  It's usually only .010".  Mark the spot where the arm makes contact with the caliper bracket and file that area.  When this is done, install the bracket.  It should be OK to split the difference between the steering arm and the bracket.  DO NOT over do it on the bracket though.  AAJ has that calculated pretty good.  Make sure you get all the gunk out of that area and especially the bolt surfaces are clean.

The next step is to prep the spindle for the Rotor.  AAJ supplies you with a spindle adaptor.  The adaptor slips to the back of the spindle.  Clean up all the grease on the spindle.  I suggest you let the adaptor sit in the warm sun before you put it on.  Apply some RED LOCKTITE to the inside of the adaptor and smear it around with your finger.  The sleeve should slide right on.  DO NOT DAMAGE the bearing or seal surface of the adaptor.  If the adaptor does not slide right on, it would be best to use the spindle nut and hub to push it it on.  Chances are, you will not need to do this.  Before you ask, there has never been a known problem of these adaptors spinning.  Remember, the cast iron expands more than the stainless steel as the wheel heats up, the adaptor will get tighter.

Prep your rotor with the bearings and seals.  Put them on and tighten correctly.

Mount your pads/caliper and hose.  Make sure you have the copper washers on the top and bottom of the hose.  You also need to be sure the notch of the hose is down so it clears the caliper and sits flush on the seal face for the hose connection. If your fitting leaks, get new washers and flip the hose fitting over. Connect the hose to the steel line.  Wipe the connections dry or use some brake clean to wash the fitting areas.  Make sure there is enough length in the hose to allow for a full swing in the steering.  Look for potential chafing of the hose too.

Bleed the brakes! Look for leaks!  DRIVE IT!    

Here's a tip if you are having trouble bleeding your brakes.  Get  piece of vacuum hose about 15 feet long.  Open the bleeder on a wheel Caliper or wheel cylinder.  Attach the hose to a vacuum source on the engine and hold the hose on the bleeder.  It is best if you have a jar in between, but the fluid will not harm the engine.  It is quickly diluted and washed away by the fuel mixture.  You'll know when the is getting fluid in it as it will start to run a bit rough.


The other item that you may want to consider is the master cylinder.  Sometimes the old single masters were called "suicide masters".  You can easily bolt on a dual master cylinder and install an adjustable proportioning valve.  If you purchase the complete kit from AAJ it includes the master and valve. 

           This is a conversion to a Bendix style booster on a 59 Chrysler

Click on Image to go to AAJ Brakes

Steve Hobby


© 2008-2014 Steve Hobby • © 2015 Allpar, LLC