The Stovebolt Site Forums The Shop Area Engine Shop GIVE ME A BRAKE!!!!

lol!! Hey, I have come across a deal, and I am curious as to the possibility of making this work: I now have in my possession a 1978 GMC 1 ton truck we took in on salvage. It has the parts I need to convert our '65 over to power steering. Now,,,I got to looking at the brakes. Do you think 1 ton front brakes would fit on a '65 C-10? I would need to change the rotor's out to 6 bolt rotors. ( It needs new rotors anyway ) Does anyone know if I can even get a 6 bolt rotor that is the same size O.D. as the 8 bolt one ton rotor? I figure if it has been done before, someone in here has done it. Thanks for the help. BTW: This salvage truck cost me $0.00 !!!

You are kidding aren't you. Have you looked at the size of that 1 ton trucks brakes. They are huge. The rotors & calipers wont even fit in the wheels of that 1/2 ton. The rear ones are larger yet. The power steering will make a good swap though.

I figured if I went to 16 or 17 inch rims, it would not be a problem. I will be using the rear brakes that came on the C-10.
I do not see anything wrong with big brakes. The downside,just more rotational mass to get going from a stop. My question was if anyone on here had DONE this before. " I figure if it has been done before, someone in here has done it "
Just looking for someone with experiance, not someone to criticize my ideas. ( That is what my wife is for. )

Hy RED65STEPSIDE, I think what Wrenchbender Ret. meant was, that is way too much brake for the front end of a half ton truck, especially if you are not going to use the rear brakes which are designed to work with those front brakes. You would always be locking your front wheels up, even on dry pavement! A better choice would be brakes designed for a half ton truck. We are just trying to keep you and everyone on the road with you safe, we're not poopooing your ideas, we're trying to point out the problems inherant with those ideas. hope that helps

I dought if any one on this websight has more experience with one ton trucks then I have, allthough I have never put brakes from one on a half ton. I'm sorry I "critisized" you. I actually thought you were putting us on, especially after you started your post with lol. I will make an effort not to answer any of your posts in the future. George

If you intend to try that project, you'll need to swap the entire front suspension, crossmember, control arms, and all. Then you'll have a totally mismatched brake system with way too much stopping ability on the front, and two different lug bolt patterns. The master cylinder for either one of the brake systems you've got would be wrong, so you'd have to come up with some sort of Rube Goldberg arrangement to provide the hydraulic pressure. There are no 6-bolt 1-ton brake rotors that I'm aware of, unless you find something like an International or Studebaker setup, possibly.

Other than those minor details that would have to be worked out, go for it!
Jerry

Cool. I meant no dis respect to you George, that is why I put that bit in about my wife! lol. But I am geting good info here. 3B voiced an opinion that I was a little worried about. (Locking up front wheels, though I was fearing in the rain.)

Sooooo, let me ask you all this: What would be wrong with installing the power brake booster/master cyl. off of the 1 ton and using it to power my stock drum breaks?

BTW: I am a christian man, and I do not EVER mean anyone any disrespect. Sometimes I can come across a little sarcastic. And I hate it when that happens. I try to be mindfull of how I word things. But it is hard to express a tone of voice on a forum. Just remember, I am new here, so you need to know ME as a person. I am a happy, easy going person. Love God and family. And have a new found love for ANY old truck! -----Kevin

Drum brake master cylinders need something called "residual pressure" in the lines to prevent air from finding its way past the wheel cylinder cups. Any residual pressure at all will cause a disc brake to drag, so a M/C for a disc system will not have the pressure check valves the drum system needs. Also, a M/C for a disc brake setup will have a much larger reservoir on the disc brake end of the system. The diameter of the master cylinder piston will almost certainly be different than the 1/2 ton cylinder, also. This affects the volume of fluid that's displaced as the pedal is pushed, and the hydraulic advantage of the M/C over the wheel cylinders will also be totally incorrect. You're betting your life on your brakes every time you push the pedal, plus the lives of everyone else on the road near you. It's much better to use brand new, correct parts for the job at hand where brake work is concerned.
Jerry

Hy RED65STEPSIDE, the main problem with using the master cylinder, is that it is for a disc/drum setup, and you need a master cylinder for drum/drum brakes [ a built in residual pressure valve for both the front and the rear brakes] you can use the booster if you like. Is the booster a vacuum type, or a hydroboost type [run by power from the power steering pump]?

Brakes are the MOST critical system on a vehicle. I wouldn't mix and match parts just because you got a donor truck. Trade the tonner for a 1/2 ton that would better suit your needs, especially if it's a dually,
Scott

Thanks for the info! I will stick to completly rebuilding the stock brake system and not fool with converting to power brakes.
Heck, the truck stopped fine for 43 years as it is. I dont guess there is any real NEED to change it. Just thought I would if i could. But after all this great info, I will just rebuild the stock breaks!

Thanks guys! ------kj

Hy RED65STEPSIDE, there are many many ways to go when "restoring" your truck, restore the original system, add a power booster to that system, convert to dual master, with or without power, convert to discs on the front, or all the way around, you get the idea. Do some surfing on the brake sites,or use the search feature here, good luck, and Merry Christmas

Just an update on the brake issue:
04/04/2009:
We just went back with the stock system. All new (non power)master cylinder, all wheel cylinders new, all new rubber lines, all new brake hardware & springs, and new rear brake shoes. ( The front shoes were nearly brand new. Evedently, my late great uncle replaced the front brake shoes just before he passed away 13 years ago.) This truck has not been driven more than 500 miles in the last 13 years. But for the first 30 years of it's life, the manual brakes worked just fine. So we figured it would be ok to just rebuild the factory system.

Do you have a rough idea of what this cost you? I am looking to do the same to my 59 apache. Any words of wisdom in doing this??? Thanks.