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Old 04-30-2015, 08:52 PM   #1
Mmorgan32
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3/4 ton disc brake conversions?

Does anyone know who sells an 8 lug front disc brake conversion with lowing spindles? I have a 70 custom camper with power drum brakes and I want to switch it to disc and lower it about 3 inches
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Old 04-30-2015, 09:18 PM   #2
lolife99
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Re: 3/4 ton disc brake conversions?

www.performanceonline.com sells drop spindles AND complete kits for the C20 trucks.
C20 drop spindles are higher priced than C10 drop spindles because there is less demand for them.
They are usually around $400 per set.
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Convert to disc brakes.
http://67-72chevytrucks.com/vboard/s...d.php?t=444823
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Old 04-30-2015, 10:51 PM   #3
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Re: 3/4 ton disc brake conversions?

Awesome thanks man. Is this how most people lower c20s? This is my first c20 I had a c10 before and it was not this difficult
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Old 04-30-2015, 11:08 PM   #4
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Re: 3/4 ton disc brake conversions?

definitely spindles , spings and shocks up front.
is your c20 a leaf spring truck or does it have coils in the back?
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Convert to disc brakes.
http://67-72chevytrucks.com/vboard/s...d.php?t=444823
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Old 04-30-2015, 11:10 PM   #5
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Re: 3/4 ton disc brake conversions?

It's leafs. I've been looking at 4 or 5 inch lowering springs but none online say if they are for a c20
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Old 05-01-2015, 07:19 AM   #6
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Re: 3/4 ton disc brake conversions?

You could send out your rear springs and have them DE-arched to provide the drop you seek. Jim
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Old 05-01-2015, 08:17 AM   #7
volksworld
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Re: 3/4 ton disc brake conversions?

eaton detroit spring made up the ones for my half ton with a 4 inch drop...sure they could do the same for a 20...they were somewhere between 3 and 4 hundred at the time ....
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Old 05-01-2015, 10:24 AM   #8
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Re: 3/4 ton disc brake conversions?

I'm doing the same thing to my C20! I've gone with air bags front and rear. Here's the kick though. My truck was a leaf sprung truck with 14! can you believe it 14 leafs on each side in the rear. It was a custom build request from my grandpa at his local Chevy dealer. He wanted it heavy duty enough to put his 10.5' camper in the back of it and tow their 17 foot boat. The truck has been in the family since birth and I remember steering it around the mobile home park while sitting on his lap when I was about 5 years old. It's now mine and I'm doing a frame up resto. I had the same setup (8 lug drum/drum) but switched to disc in the front at some point in the '90's. If you're on a budget and just want to get to disc brakes first just find a 3/4 ton 73-87 at a wrecking yard and nab the whole spindle with the rotor and calipers. It will bolt right onto yours. It sounds like the best thing to do for you though would be to get the C20 lowering spindles from performanceonline and just go with all new parts up front. need, rotors, calipers, brake hoses, inner, outer bearings, races and grease seals, a disc drum master cylinder and prop valve. you'll also want (although I didn't, but I plan to) to re-plumb the front brake hard lines. the drum brakes go from the master to a T and then out to the wheels. No proportioning with this setup. At least on mine. With the disc setup the master goes to the prop valve and then out to each wheel separately.
The rear feed stays the same pretty much. I've been a mechanic my whole life and been working on this particular truck for most it . I'm excited to hear of the lowering of another 20.
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Old 05-01-2015, 10:32 AM   #9
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Re: 3/4 ton disc brake conversions?

So I would have to change my master cylinder even though I have power brakes? Would I have to change the master if I pulled the pindels and discs from a 73-87 or just add a proportional valve?
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Old 05-01-2015, 10:45 AM   #10
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Re: 3/4 ton disc brake conversions?

Yeah, the masters are different visually as well as how they work. The drum/drum master is proportioned internally to be 50/50 pressure and the disc drum is about 70/30. Also the disc master has a larger reservoir for the disc portion to allow for the higher fluid demand from having calipers instead of wheel cylinders.
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Old 05-01-2015, 10:50 AM   #11
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Re: 3/4 ton disc brake conversions?

You can get driving without doing the master however it's a good idea to do it. I changed mine way back in high school on a budget and just did the spindles with rotors and calipers. it stopped way better than with the drums but still not like other trucks with the disc brakes already on them.
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Old 05-01-2015, 10:56 AM   #12
Greg924
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Re: 3/4 ton disc brake conversions?

I'm doing the same thing to my C20! I've gone with air bags front and rear. Here's the kick though. My truck was a leaf sprung truck with 14! can you believe it 14 leafs on each side in the rear. It was a custom build request from my grandpa at his local Chevy dealer. He wanted it heavy duty enough to put his 10.5' camper in the back of it and tow their 17 foot boat. The truck has been in the family since birth and I remember steering it around the mobile home park while sitting on his lap when I was about 5 years old. It's now mine and I'm doing a frame up resto. I had the same setup (8 lug drum/drum) but switched to disc in the front at some point in the '90's. If you're on a budget and just want to get to disc brakes first just find a 3/4 ton 73-87 at a wrecking yard and nab the whole spindle with the rotor and calipers. It will bolt right onto yours. It sounds like the best thing to do for you though would be to get the C20 lowering spindles from performanceonline and just go with all new parts up front. need, rotors, calipers, brake hoses, inner, outer bearings, races and grease seals, a disc drum master cylinder and prop valve. you'll also want (although I didn't, but I plan to) to re-plumb the front brake hard lines. the drum brakes go from the master to a T and then out to the wheels. No proportioning with this setup. At least on mine. With the disc setup the master goes to the prop valve and then out to each wheel separately.
The rear feed stays the same pretty much. I've been a mechanic my whole life and been working on this particular truck for most it . I'm excited to hear of the lowering of another 20.
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