Drum brakes on a 1979 Big 10?

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Grit dog

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That's as close to a question that's never been asked as I could imagine...
I'll have to answer a question with a question.
WHY?
 

Goldie Driver

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1. Room for a 15X3.5 draglite rim
2. Less drag
3. Weight

I'd actually be curious to see what the weight difference would be between the drum brake hardware and drum versus the rotor, pads, and caliper.

Having said that, to the best of my knowledge all the squares had disc brakes up front. To go to drum I believe new spindles would be required - not sure if the prior generations would work or not.

I'd also assume that a new drum brake proportional valve would be required.

I am not a fan, but would Centerline wheels be an easier solution?
 

Mark Jones

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I'd actually be curious to see what the weight difference would be between the drum brake hardware and drum versus the rotor, pads, and caliper.

Having said that, to the best of my knowledge all the squares had disc brakes up front. To go to drum I believe new spindles would be required - not sure if the prior generations would work or not.

I'd also assume that a new drum brake proportional valve would be required.

I am not a fan, but would Centerline wheels be an easier solution?
I was thinking my caliper would hit the back of the rim, but after looking at it again I think it will clear, redrilling my rotors for 5/4 3/4 pattern.
 

Turbo4whl

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1. Room for a 15X3.5 draglite rim
2. Less drag
3. Weight

Keep the disc's

#1 Add a wheel spacer, or grind metal off the caliper.

#2 Loosen the front wheel bearing adjustment. GM's original design for disc brakes called for a looser adjustment. The slight wobble pushes the pads back.

#3 Buy aluminum/ alloy calipers.
 

nabeshin

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Might as well get a wooden block on a lever to drag on the tire like some old stage coach.

Anyway, disk brake piston seals are designed to pull the pads back ever so slight so that they do not drag/stay on until worn clear.
 

Turbo4whl

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Might as well get a wooden block on a lever to drag on the tire like some old stage coach.

Anyway, disk brake piston seals are designed to pull the pads back ever so slight so that they do not drag/stay on until worn clear.

Yes, newer designs always have improvements. GM service manual/bulletin in the early 1970's clearly stated, looser adjustment on the wheel bearings.
 

Ricko1966

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I thought he already decided against going drum because he saw he had the clearance he needed.But if you want to you can use 67-70 c spindles,brakes,balljoints,hoses,outter tie rod ends, master cylinder. And proportoning valve.Lots of work and money, but it's your truck and your time and money.
 

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#2 Loosen the front wheel bearing adjustment. GM's original design for disc brakes called for a looser adjustment. The slight wobble pushes the pads back.


That's one of the craziest things I've ever heard, that actually makes sense.
 

Ricko1966

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That's one of the craziest things I've ever heard, that actually makes sense.

It's also a sign of worn out wheel brgs, you go around a corner or hit some bumps and your pedal height is low like there's air in the lines, but nope the rotor leaned and pushed your piston in.
 

Mark Jones

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Keep the disc's

#1 Add a wheel spacer, or grind metal off the caliper.

#2 Loosen the front wheel bearing adjustment. GM's original design for disc brakes called for a looser adjustment. The slight wobble pushes the pads back.

#3 Buy aluminum/ alloy calipers.
Thanks for the info, actually my rotors are very free turning, just need to get the 15X3.5 rim on there.
 

Mark Jones

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I thought he already decided against going drum because he saw he had the clearance he needed.But if you want to you can use 67-70 c spindles,brakes,balljoints,hoses,outter tie rod ends, master cylinder. And proportoning valve.Lots of work and money, but it's your truck and your time and money.
Thanks for the information! If I can't get the rims to clear the calipers thats what I will do.
 

Ricko1966

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Thanks for the information! If I can't get the rims to clear the calipers thats what I will do.
Wheel spacers would be so much easier and cheaper, if you don't like the aluminum ones readily available. I have made my own before, take a junk rotor or drum, stick it in the brake lathe and turn it until it's just a 6 inch plate with holes in it.
 

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