3/4 Ton Brake Drum Fix

From: Freddy Badgett
via the Studebaker Newsgroup
 
In my cluttered fix-it files I have found the part number for the seal needed to put Dodge 3/4 ton 8 lug rear brake drums and backing plates on a 3/4 ton Stude truck.  The original drums may be non-existent. Here is a brief description of the fix I did on my 59 4E12.  

Studebaker used Dana rear axles, as did Dodge. I used rear drums, hubs and backing plates and all brake hardware from a 71 Dodge 3/4 ton (They may call those a 1 ton in van applications) Many other years may work as well, those drums are THICK! The backing plates and brakes are @1-1/4 inches wider (More Brakes!!), the extra width goes inboard toward the rear leaf springs. Find the drums with the same machining "look" as the old ones a where the hub shows thru the wheel. On mine, the bearings were interchangeable, so I cleaned repacked, and used the Dodge bearings, being careful to keep them mated with the races they had ran on all their life. With the old drum and backing plate removed, test fit the replacement backing plate-you will probably need to grind a very slight notch to clear the wheel cylinder at 12 o'clock on the rear end housing flange where the interference shows - it only takes a little, don't over do it. My Emergency brakes are driveshaft mounted, the Dodge had E-brake hardware in each rear backing plate, so adapting that is up to you. While the Dodge drum/hub assembly is in hand, use a ball peen hammer to cut an outer axle flange to hub gasket (where the axle meets the hub) from an aluminum throwaway pie pan-the thinner the better! (old racecar fix, those were a bear to seal, the aluminum was better than anything we could buy!) The metal brake line tubing will screw in the dodge w/cylinders, but a slight bend is needed to shorten them, to take up for the wider backing plates. The Dodge hub and drum has a larger inside diameter than the Stude where the seal is driven in-the Stude axle housing has a smaller diameter surface for the inside of the seal to ride on. Here are the numbers-National seal number 410825 ( the parts guy said this was a popular -in-stock item, therefore cheap!) The measurements I used are as follows: I.D.-2.375 -O.D.-3.623 - Width- 0.375

The Dodge w/cylinders are cheap... er-Frugal...and, by drilling one hole in the FRONT backing plate at 2o'clock, those w-cylinders also can be used on the front of a Stude truck (Well, it fit my 59 pretty well, and they may fit a 1/2 ton!) Use the Stude Brake hardware, (save those metal plungers that push the shoes!!) and the cheapo newer Dodge wheel cylinders ($9.99 at local parts store) fit well, and many different inside diameters were available. Stude Parts/repair manuals may confirm how many years used the same mounting pattern. The wheel cylinder ID (Inside diameter) is an issue-that must be matched up to the original unless you want more front brakes,then a slightly larger ID will increase front stopping force.

No guarantees, expressed or implied!

Freddy Badgett

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