The Stovebolt Site Forums The Parking Lot Big Bolts 2 ton disc brakes

Has anyone ever seen a disc brake kit for a 2 ton 49 6400? I have done a search in past topics, but didn't run across any for the big trucks. What kind of other sized rotors would bolt up to my 5 bolt front end or 10 bolt rear end? Thanks in advance for any info.

I have never seen a kit for your application, but it's probably possible to do it. I'm curious. Why do you want to do this? Are you changing the rest of the truck with a bigger motor, etc.? If you are leaving the rest of it stock, I would think the regular drum brakes with the booster would be more that adequate. Allen

Modern wheels to fit your current hubs are a problem. There are some that are close but I'm not sure exactly what they come off of.

That's important because the brakes to fit your existing wheels are going to come off something your wheels would fit.

Or are you planning to change wheels also?

If so then the possibilities for brake swaps open up a bit. I've not seen a kit for a 4000 or 6000 series truck and I doubt you will find one. There are not enough people wanting to make this swap to justify engineering and tooling to market a kit.

If you can find disks that make sense you can then start solving the hub, bearing and caliper problems.

I've thought about putting disks on my '52 6400 but have decided the way I use this truck there is no good reason not to stay with the stock drum brakes.

If you come up with a solution please share it here. I'd sure like to know if there is an answer.

search past post for "Dana 70HD"
That should bring up some stuff about the conversion I did to my 1 ton. My new stuff will fit 1.5 and 2 tons also, I plan to switch it to a 2 ton frame soon.
Your choices are to change the whole front axle, or modify your axle ends to fit newer spindles with disc.
Any questions Just ask.

Grigg I have a question.

I have a 1-ton (3800 panel), a 1 1/2-ton (4400)and a 2-ton (6400) sitting in my yard. I don't really want to convert the 2-ton but it does represent some of the parts I have on hand.

I want an 8-lug disk brake conversion that will fit under the 1-ton front fenders using dually type wheels.

Do you know anything that might suggest I should start with one of these axles instead of another? I have a complete P30 sitting in the yard also, and since I plan to use the rear axle from it, the disk brakes on it's front axle would be my first choice. Its an IFS, and I'm not convinced putting that under this truck would be the best approach.

Any ideas?

OldSub,
If I understand you correctly you want 8 lug disc for your 1 ton, and nothing done with your 1.5 or 2 ton. You have a P30 for the rear (assuming it is 8 lug) that will work on your panel?

So, you could use the disc brake rear, if the wheels fit the body? And for the front I would suggest the I-beam front axle with 8 lugs and disc from some other P30. I see twice as many of those driving around here than I do independent or 5 / 10 lug ones. however, they usually have 19.5 rims, not sure if smaller ones will fit over the calipers, but the 8R19.5 tires just fit the 1 ton front fenders if you chose.

This would require narrowing the front axle, I can't think of any axle that is already narrow enough with disc brakes. Or, use your I-beam and adapt everything else to fit, I have seen that done with the 5 lug spindles. And I have heard about someone in Texas using dodge 8 lug parts, do a search on this site for that.

In summary, no real simple answer, and lots of decisions to make. Anything I can make more clear?

Grigg,

I've corresponded with the guy in Texas about his swap. He put Dodge rotors on the stock hubs and made his own caliper brackets.

1-ton disk brakes

He also put a Cummins Diesel in it also.

My P30 is wearing 16-inch wheels and I'm happy with those.

I think the 1-1/2 ton is just going to be parts and could contribute a front axle to this project.

I'm building a dually pickup using the rear of the panel to make a pickup bed. The P30 rear is part of the plan, and the disks off the front of it could be part of this project too.

My 1/2-ton Suburban has 5-lug disks on a straight axle. I used a kit for that conversion but figure I'm on my own for this one.

Sounds like you have a plan, just need to find a donor for the front disc and or a complete axle.
Let us know what you find. And I'll keep my eyes open for a sutiable 8 lug disc I-beam front.

I have a 10,000 foot plan. I need to get the details worked out yet...

Please do let me know if you see something that looks like it would work.

Sorry for the delay in responding.....I drive a UPS truck and I have had trucks with both drum and disc brakes. The discs stop so much better; thats kind of the reason I wanted to upgrade. I am not planning on changing engines, but my UPS truck goes a little faster than my 6400(which dosen't go anywhere now). Maybe with such a speed diference, I wouldn't need an upgrade after all. What do you experienced guys think?

I wish I were experienced but my 2-ton has never had working brakes...

Maybe I'll fix that soon, but its behind several other priorities.

In my youth I drove similar sized Ford trucks for a farmer. I remember hauling 12,000 pound loads and feeling confident it would always stop even though it only had drum brakes.

If you are not going to make it go faster than stock, and not going to over load it, I think a good working drum brake system with a hydravac should be more than adequate. If the truck is otherwise stock keeping the original brakes should be fine.

I'm certainly not an expert on this subject, but I am old enough to remember when these trucks were in general use, and I don't ever remember their being a problem with the brakes. They were used for everything you can think of, because that is all there was, and I don't remember brakes being an issue. Getting up a long hill with a heavy load was another matter. They always got there, but it was best not to be behind one unless you had a little time on your hands. Allen

I'll take the other side. I'm a big fan of having the best brakes possible. Saying you haven't heard of anyone having a problem stopping with the stock drum brakes is like saying you have proof deer whistles work - you can't prove a negative. I HAVE had drum brakes fail on me (though not on a 'bolt). The linings - which were riveted, not bonded, fractured and came off the shoe under a hard stop. Definitely NOT fun. Drum brakes also have a big problem if they get wet - centrifugal force traps the water on the inside of the drum, where it hampers braking action. Disks are self-cleaning. Finally, when the drums get hot under heavy braking they expand, which reduces braking action and requires additional pedal travel. When disks get hot they shorten pedal travel and increase clamping force.

If you plan to leave your truck totally stock and only drive it to shows and cruise night, leave the brakes stock. If you plan to use it as a driver and a work truck, I'd upgrade the brakes. I certainly plan to.

Joe Padavano

Joe I'm going to suggest there is a reason leaving the brakes stock might be superior to upgrading to disks.

But first, I've seen disk brakes fail because of inferior or worn parts, and I've had them fail because they were wet. The are not immune to problems, just react a little differently.

Some of the disk conversions I've seen looked dangerous. And on a big truck, the risk of brake failure with a loaded truck is scary enough that I'd feel safer believing the old trucks out there have well-maintained stock brakes rather than back-yard engineered disk conversions.

Done right either will stop a truck and done right disks are usually superior, but I like the idea of stock drums on an otherwise stock truck over a questionable conversion.

I'll say that I like the disc on my 52 1 ton, but they are not necessary. I drove the truck for a few years with the original brakes and they always worked and I was confident they would. Now that I have disc I find my self stopping later and faster than I did with the drums.... not that that's a good thing. I plan to go fast one day, and then I will be really thankfull for the disc brakes.
If you don't change the gears or the HP stock brakes are great.

Steve,

I agree that there are many scary disk conversions out there and that poorly maintained vehicles can fail no matter how well engineered they are. I'm also sure that the stock brakes are fine under normal use. My concern is under panic conditions. Stock HP isn't an issue; when going downhill with a full load gravity will far outweigh the HP. Mine is destined to be a work truck, not a show truck and I want to be sure brakes are not an issue. The 3500HD setup similar to what Grigg has done is very attractive in my opinion.

Joe I have a K3500. It weighs more than 5,000 pounds with a GVW of just over 8,000 pounds.

My '52 6400 weighs about the same, but has a GVW of 16,000 pounds.

My P30 (forward control 1-ton chassis) has a GVW of 12,000 pounds. It's a motorhome and I'm sure weighs a lot though I don't know how much.

So if I load my 6400 like it was designed to be, and then try to stop it with brakes designed to stop half the weight (my K3500), I could be in real trouble. And the brakes from the P30 might be better, but not better enough.

If you convert to disk brakes, make sure you are using stuff designed to stop something with your true GVW. Otherwise you might be unpleasently surprised someday.

Going downhill in an big truck I've always made sure I was in a low enough gear the truck could not go faster than my brakes could handle.

Be safe! Over engineer your brake conversion.

If you take brakes from a 3500 adjust your GVW to match the 3500 donor.

Steve,

I agree with you cautions on hardware selection. The late 90s HD3500 used a beam front axle and Dana 70HD rear with four wheel disk brakes. These trucks can be identified by their 10-bolt wheels vs. the 8-bolt wheels used on the normal 3500 trucks. GVW on the HD3500 is 15,000 lbs (actually there were three versions at 11K, 12K, and 15K, but all use the same brakes - the differences are in the frame reinforcements). Even more important than GVW is individial axle weights. By the way, both my 99 K3500 and my 86 K30 (both duallies) have 9,990 lbs GVWs.

I'd probably accept that brakes designed for a modern truck with a 15,000 GVW would probably be good enough for something like my 16,000 GVW 6400.

My K3500 is not a dually, but you knew that from the GVW. I thought about a dually, but wanted to drive the truck everyday and an extended cab pickup with an eight-foot bed can already present parking challenges. Make it more than a foot wider and it gets worse, as I'm sure you already know. I pull a car trailer with it that has never challenged the truck, so I feel it was the right choice for me.

One of my projects is creating a dually pickup with a style-side bed based on a '53 GMC panel and parts of a Chevy 1-ton panel. The frame I plan to put it on was marked with an 8800 GVW and my brakes are coming from the 12,000 GVW P30.

Anyone have a picture of a disk brakes on a duel rear wheel 16,000 GVW truck from the 50's?

Look at the pictures in my link below, my setup is shown with single wheels, but I will put duals on it in time... same wheels as I now have on the front.

Grigg

This article here on 4x4 mag website is showing a kit for a 1 ton axle:

http://4wheeloffroad.com/2005ultimateadventure/131_0510_uak5/index1.html

made by these folks:

http://www.offroadunlimited.com

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Anyway, I stumbled on this reading the article and I recalled this thread.

-W