The Stovebolt Site Forums The Parking Lot Big Bolts 1948 2 ton Front disc brake conversions

This is as close as I could get to the forum I was looking for. It was in the big bolt section which is completely gone. I was doing some research using AI on how to convert a 1948 Chevrolet 2 ton to front discs and I did come up with some interesting results, but before I spend a pile of money following AI, I would like some “real world “ knowledge from those who do. Besides, I’m claustrophobic after being pinned under a trailer and I want to get in get it done and get out!

Sweetietheswede - I got your post back into Big Bolts as it's own thread so folks can offer some insight and suggestion/real world experiences as you say. Folks should be along soon.

While you await others to reply, you might consider reading through this older on topic thread by Bolter Grigg. It has a ton of information that is much the same these days as it was back when he first put this together.

Is there a compelling reason to switch from drum to disc brakes? If the concern is difficulty in sourcing original parts, wouldn't it be simpler to swap to a later model, more available drum brake setup? Is the vehicle being used commercially, or has it become a "Cowboy Cadillac"?
Jerry

Huck brakes just aren't great. And they're less great under a heavier rig. I'm not sure how much the disc brake kits are, but I can tell you how much a pair of new 14x2.5" Webb brake drums are.. like a thousand bucks. And that's after buying the Bendix brake backing plate, shoes, hardware, wheel cylinders etc.

I went the brake drums route because the rest of my setup was already in decent shape, save for the usual wear related repairs and cleaning of the backing plates. However, if I were doing it from scratch I'd definitely consider spending my money in the right place, in the first place-on a modern setup for which you can get parts and which, frankly, will stop a lot better especially in the wet.

With the explicit understanding that modifying brakes can result in far more harm than your kids being born naked, while making a lot of power boat payments for the right ambulance chasing attorney.. it's now been done enough that people know what works and what doesn't, what's safe and what isn't. It's a conversation worth having if you're gonna keep the rig long term, and/or give it enough go to exceed the 50mph factory top speed whoa provided by those Huck brakes.

I remembered Grigg experimenting with a Chevy 3500 HD axle outer brake, and steering knuckles, and adapting that to a 2 ton axle. I ended up chopping and shortening the P 30 axle which is the same as the 3500 HD. I had a 2 ton axle. I would’ve loved to play with that myself.

I built my own brackets and used Rotors from a 2000 Chevy TopKick and Calipers from a 2015 F@&d F450. Tied that to a Hydro-booster and Dual Master Cylinder form a 1990 GM Motorhome. Used the the rear axle from the Motorhome as well, so 4 wheel disc brakes. Truck stops like NOW.

TUTS 59, was it a challenge with the set up you created to get the same width of the spindle/rotor/spacer assembly and overall WMS measure/ tire fit in fender as the original brake set up had? I would like to replicate your set up. It’s very hard to find P30 or c3500hd parts for Grigg’s setup.

No, the spacing is factory. In fact I used the original hubs and adapted the Rotors to them. I did upgrade the bearings to the more modern tapered roller cone style.

The entire set cost less than $500.00. It did take some head scratching to work out the brackets. I made everything with hand tools, a cutoff wheel and grinder and drill.

Was the Topkick rotor of the same inner diameter as your hub, in other words did it center up the same as the original drum?

The Topkick Rotor is Hub Centric and had the same ID as the front Brake drum. The Rotor has 12 bolt holes and the factory hub has 6, the holes lined up correctly. I used Grade 8, 7/16 x 20 Bolts and steel lock nuts with Red Lock Tight to secure the Rotor.

Please keep in mind that I have a '59 1.5 Ton, the hub may be smaller than a 2 Ton version. I used Rockauto.com for a research source, they have very detailed descriptions. BE SURE TO MEASURE EVERYTHING...

FYI guys, the Hollander interchange manual shows the 54 2 ton as having the same hubs as the heavy duty version of the 55-59 1 1/2 ton with a heavy duty front axle. The medium duty front axle for 55-59 is not the same as the 54 2 ton.

46-53 2 ton front hubs are the same as 51-52 1 1/2 ton and 53 1 1/2 ton with a heavy duty axle

Front Brake drum interchanges for reference

Looks great! Could you provide the rotor and calipers (and hoses) part numbers? Then it's just a matter of a guy working out the brackets. Thank you!

The part number are as follow.

Rotor; Rabestos 960066R, 2000 Chevrolet Tiltmaster

Caliper; Ultra Power 18B5487, 2015 F@&d F350 Super Duty.

Seems the key to making TUTS 59’s setup work for different years and weight ratings is hub size of your model. Haven’t taken my 54 2 ton apart yet to get exact measurements but the rough crude measure I did with wheel still on tells me my hub is very similar in size to fit a tilt master rotor. Of course crude measure is not good enough, so maybe if everyone measured their hubs from different years and weight ratings we could get a list going here with what rotors can work on our trucks. Thanks TUTS 59 for sharing your fix, hope to put it into use at some point.