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Old 04-11-2011, 09:15 PM   #1
airbrushguy
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Power Brake Booster

I have a '71 C10 with 250 6cyl and disc brakes. I don't like how much pressure I have to give to make it stop so I'm going to add a power booster.
If I go to the junkyard, what years and models are interchangeable with my system?
Thanks
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Old 04-12-2011, 07:00 PM   #2
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Re: Power Brake Booster

Ttt
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Old 04-12-2011, 07:07 PM   #3
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Re: Power Brake Booster

If peddle effort is the problem, you have a brake problem. Even without power assist, the effort shouldnt be a big deal. but 2 answer your question,
i think that the 71 and 72 trucks are the same. the booster may be the same on some later trucks but the brackets are not correct.
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Old 04-12-2011, 07:42 PM   #4
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Re: Power Brake Booster

" Even without power assist, the effort shouldnt be a big deal."
I replaced pads, rotors, wheel cylinders and all lines....still is tough to stop.
Any thoughts?
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Old 04-12-2011, 07:56 PM   #5
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Re: Power Brake Booster

Bleed the brakes?

Just askin' the obvious.

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Old 04-12-2011, 08:46 PM   #6
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Re: Power Brake Booster

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Bleed the brakes?

Just askin' the obvious.

Gary
Of course, and not my first time ever doing it.
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Old 04-12-2011, 09:12 PM   #7
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Re: Power Brake Booster

I know it's a dumb question but have you driven a manual brake rig before? assumeing that you have not, remember it takes longer and more leg pressure for a manual brake to stop the rig then a power brake rig

If you have ignore the earlier

71-72 should be a fit but there must be somthing wrong with the master. it may be rusting internaly or debris could be causing the hard pedal
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Old 04-12-2011, 09:32 PM   #8
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Re: Power Brake Booster

My son's 68 has disk front brakes w/ no booster. My two other trucks (69 All drum and the 71) do have boosters. His truck doesn't put you through the windshield but does stop really decently. Not sure what you were expecting but is it possible the MC or prop valve could be changed to improve your brakes? Not much of a fan of using junkyard parts when it comes to stopping but finding the proper booster brackets you will need will be on the 71/72 trucks.
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Old 04-12-2011, 09:47 PM   #9
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Re: Power Brake Booster

I guess it might be the MC...yes I am used to manual brakes...been driving and working on cars for 40 years.
I had a 66 Mustang, took almost two feet to stop its non-power brakes.
When I bought this truck I wondered if the brakes should be this tough so I replaced everything but MC. Friend has a '70, he told me he put on booster because brakes sucked.
Should I be able to stop easily with normal pressure without power booster?
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Old 04-12-2011, 10:11 PM   #10
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Re: Power Brake Booster

my suburban is a power brake truck both my econolines are manual drum brake rigs and I can stop them both very quick but I work in the construction field so my legs are strong.
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Old 04-12-2011, 10:28 PM   #11
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Re: Power Brake Booster

ok since you have replaced pads and lines and stuff, 2 things come to mind.
1. did you check to see that the front calipers are free to float?
your calipers can be hanging up on the through bolts and not centering themselves when the brakes are applied. this can cause the hard peddle.

2 are the rear brakes adjusted properly ?
if one of these 2 aren't the problem, i'm stumped.
best of luck, Tony
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Old 04-12-2011, 10:54 PM   #12
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Re: Power Brake Booster

If you been working on vehicles for 40 years you might be almost as old as me. so one old guy to another you know you are asking for trouble getting used master and booster from a junkyard, you will just end up putting more money in it when you realise it needs rebuilt or some such, so just break loose with the wallet and go get a 3/4 ton booster and master cyl new/ rebuilt from the parts store. You can likely find the brakets and bell crank assembly on the parts board here. the 3/4 ton is a good uprade for a C10 like I did on this little K10. This is what the bell crank and brakets look like that you'll be needing
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Old 04-13-2011, 12:47 AM   #13
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Re: Power Brake Booster

Gringoloco has a build where he uses a 3/4 ton booster (dual diaphram, smaller diameter) with 1/2 ton master............
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Old 04-13-2011, 06:40 AM   #14
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Re: Power Brake Booster

CaptainFab is a vendor on the board and he sells a short braket that allows the use of the newer 88-98 truck booster....

http://www.67-72chevytrucks.com/vboa...d.php?t=347484
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Old 04-13-2011, 06:48 AM   #15
airbrushguy
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Re: Power Brake Booster

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Originally Posted by Olden Days View Post
If you been working on vehicles for 40 years you might be almost as old as me. so one old guy to another you know you are asking for trouble getting used master and booster from a junkyard, you will just end up putting more money in it when you realise it needs rebuilt or some such, so just break loose with the wallet and go get a 3/4 ton booster and master cyl new/ rebuilt from the parts store. You can likely find the brakets and bell crank assembly on the parts board here. the 3/4 ton is a good uprade for a C10 like I did on this little K10. This is what the bell crank and brakets look like that you'll be needing
You're right and I probably will buy new. But I guess what I really wanted to know is "interchangeability." I'm frustrated at the performance of these brakes without a booster and wondered if I could test the value of adding power brakes before throwing $300 or so only to find its more of a mechanical failure than need of booster.
I have found many posts saying the brakes on these trucks aren't great but having lived through '71 and the introduction of front disc brakes as standard equipment I find it hard to believe this trucks ability to stop on a dime is so poor.
I would rather put a booster on to make it easier than to overcome some mechanical malfunction that I overlooked.
Thanks
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