'66 3/4ton add power brakes...

[sandman]

I have picked up a '66 3/4 ton truck. It has manual brakes with single master cylinder brakes and a Dana or Dana/Corporate rear axle.

My question is looking for an relatively easy way to fix the brakes. I have a couple different directions I could possilby go. So I need

I don't think that the conversions to disk brakes are the right way to go, for me, as the aftermarket kits appear to be all 1/2 ton. I assume that a donor 3/4 ton in the 1973s - 1987 range would provide the parts I need, however, my wife of 42 years would probably not make it to 43 if I had any more vehicles laying around the yard.

Therefore, I had in mind ordering a drum/drum master cylinder and power booster for a 3/4 ton in the 73-87 range and doing a bit of replumbing. That should give me power drum brakes and a dual master cylinder for safety. I have lost the master out of a single brake system a couple of times before and have no interest in repeating that action.

Am I basically on the right track? Does anyone have any part numbers or awareness of potential snags?

Thanks in advance........

[zenish]

try asking at www.chevytalk.com

[BobS]

Sandman,

You'll need the master cylinder from a 67-70 3/4 ton, from 71 on all front brakes are discs. Make sure your booster matches the master cylinder, there are tow different lengths of push rods. Converting to 8 lug discs on the front is pretty simple, you don't need to buy a donor truck. Just sneak off to a salvage yard on Saturday afternoon and hide the parts in the garage, your wife never needs to know!

Bob

[sandman]

Originally Posted by zenish

try asking at www.chevytalk.com

Thanks....I will wander over there this afternoon......

[sandman]

Originally Posted by BobS

Sandman,

Converting to 8 lug discs on the front is pretty simple, you don't need to buy a donor truck. Just sneak off to a salvage yard on Saturday afternoon and hide the parts in the garage, your wife never needs to know!

Bob

I like your style.....thanks for the answer...

I will assume that ordering a power booster with master cylinder (there is one offered like that at Autozone) should give me the proper length pushrod. Are you aware of any firewall problems......other than wiring behind it?

[zenish]

i haven't been able to find a new booster for my 64 c10.maybe the c20s are different.

[BobS]

There's an original on Ebay right now with a dual master cylinder but it's missing the aluminum wedge-shaped piece that mounts between the booster bracket and the firewall. Item number 4614824645

http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMEWA%3AIT

Here are some shots of how it's supposed to look:

http://community.webshots.com/photo/...56812367TiQsYO

http://community.webshots.com/photo/...33760087zpUcrS

http://community.webshots.com/photo/...56812367znAXFR

Does the AutoZone kit have the mounting brackets and pushrod to connect to the brake pedal?

I'm adding power brakes to one of my trucks now, I can let you know in a few days about the firewall issues. There's no wiring stuff to worry about but I have to check to make sure that the brake/clutch pedal bracket isn't different at the firewall for the booster mounting bracket on the engine side.

Zenish,

I saw new boosters somewhere recently they were about $165 IIRC. I'll let you know when I find it back if you're interested.

Bob

[sandman]

Thanks to all of you who posted answers. You have given me some stuff to mull over. After I figure out which way I will go, I will come back into the thread and add what I have done in case someone else needs the info later....


Thanks again, all...

[zenish]

thats the one i need but i don't want a 40 year old booster.whats llrc?

[sandman]

Does the AutoZone kit have the mounting brackets and pushrod to connect to the brake pedal?

Autozone does not have a kit, they have a power booster with or without a dual master cylinder for just under $135. The core charge is different. I used a '69 Chevy 3/4T 2WD for my search so I assume that it is a dual master since dual master was standard starting in '67. The listing asked if it were for disc front brakes or drum fronts. Here is the info:

Cardone Power Booster w/o MC 54-71011 Core 18 Price 92.99
Cardone Power Booster w/MC 50-1011 Core 35 Price 99.99

I'm adding power brakes to one of my trucks now, I can let you know in a few days about the firewall issues. There's no wiring stuff to worry about but I have to check to make sure that the brake/clutch pedal bracket isn't different at the firewall for the booster mounting bracket on the engine side.

Pedals would also be a concern to me.


Zenish, I also found that there is a place called Jim Carter's Truck Parts who has what appear to be 63-70 3/4T conversions to disc. They are asking 899 for the kit with no MC or power booster, but also have the MS/PB kit with mounts, etc.. for 399. There URL is:

http://www.oldchevytrucks.biz/catalog2/0052.html

Bottom of the page - P/N HP524

On the previous page are the power boosters.

P/N HP552.

I saw new boosters somewhere recently they were about $165 IIRC. I'll let you know when I find it back if you're interested.

Bob

Thanks........

[zenish]

i could get that but all i need for the factory setup is the booster.ive got the brackets.

[BobS]

Zenish,

IIRC-If I Remember Correctly.........I didn't, it was $150 plus $30 for the core and it was LMC that had them listed. Not sure of the quality.

Sandman,

I'll check my pedals this weekend and let you know if there's a difference.

Bob

[BobS]

Pedals look like they are the same and the pedal bracket on the inside of the cab has the provisions for the factory booster mount.

Bob

[jgrh64]

[QUOTE=BobS]Sandman,

You'll need the master cylinder from a 67-70 3/4 ton,

Everone is mentioning the original booster has a triangular bracket on firewall ,I want to switch to power brakes but do not have a bracket - is there some way around using this bracket ???

[BobS]

I don't think you can use the factory setup without the aluminum bracket but if you were willing to do some fabricating it looks to me like a 67 and later setup could be adapted. There are also kits where everything to do the conversion is included, that may be cheaper in the long run. I can send you pics of the factory setup, it's all still sitting in a box, I haven't had much time to play with the trucks lately!

Bob

[hedges]

Sandman ,
The classic performance tech section has some info and pics on this.
It's under the title 'Power brakes for 1960-66 ChevyGMC trucks'.
http://www.classicperform.com/tech.htm
Dan

[sandman]

Originally Posted by hedges

Sandman ,
The classic performance tech section has some info and pics on this.
It's under the title 'Power brakes for 1960-66 ChevyGMC trucks'.
http://www.classicperform.com/tech.htm
Dan

Thanks, Dan, for the comeback. The problem with that setup is that it maintains the single master cylinder which is not what I want. Their other notes on that page concern a disk/drum setup.

I have an Email into CPP (and one into Master Power Brake) to see if their booster is compatible with a 67/70 3/4T drum/drum master and has a pushrod that will work in that combo. That way, I can order the proper master cylinder from Autozone, for example, not be bothered by any bracket problem.

I will post when I get the answer from them.

Again, thanks for your post......

[Shorty Cox]

Sandman, What are you going to do with the truck? Is it for show or a driver? I ask this because I was ask the same question a few years ago when I was considering making the change to power brakes on my '64. I was with a group of "ole shadetree mechanics" disucssing old pickups when I was ask, "Have you had trouble stopping you truck now?" To which I answered, NO. Then i was ask, "The brakes on the truck have been stopping the truck for 38 years, why change now?" Well, I chose not to spend the money for the upgrade and the oldtimer was right. My ole'64 has been stopping for 42 years now without a problem.

But, to each his own...If you wish to spend the money, do so.

[rtsmith]

Originally Posted by hedges

Sandman ,
The classic performance tech section has some info and pics on this.
It's under the title 'Power brakes for 1960-66 ChevyGMC trucks'.
http://www.classicperform.com/tech.htm
Dan

Thanks Dan i have been looking for the 8 lug disc brake setup and the site had them now I can get moving on my 68 chevy C20.

[sandman]

Originally Posted by Shorty Cox

Sandman, What are you going to do with the truck? Is it for show or a driver? I ask this because I was ask the same question a few years ago when I was considering making the change to power brakes on my '64.

It will be a driver. The main reason I am looking into the change is simply peace of mind. I have had brakes go out on me before. My reflexes simply ain't what they used to be. I realize that they stopped rather well when the truck was new but I like the split circuits for the reason of safety. I like power brakes since I have simply become used to them over manual ones.

I converted my '72 "FJ40 from drum/drum to power 4 wheel discs and love the result. My '69 Chevy 1/2T has been converted to disk/drum. When we get those old rains out here in Arizona (if we ever do again ), drums are instant fade when you have to transverse those washes.....disks get back into action a lot quicker.

All in all, I prefer disks over drums but in the 3/4T arena, most of the kits are 1/2T and, I suspect, that even the ones with 8 lug rotors are just 1/2T units with the additional rotor. If I hear different from CPP or Master Power I will be quick to post that news in this thread.

Hope that answers your question. I agree that manual, single circuit brakes work and some work quite well, but.......

[hedges]

Sandman,
CP lists kit - 6366BBD as a drum/drum solution so they should be able to help. (I've seen their kits on ebay for less)
It also looks like they sell the booster, master clinder and proportioning valve seperately. The NAPA web site carries boosters but only single bore master cylinders for these trucks. Maybe they can xref the booster across years for you and recommend a later year mc that will work.
I've picked up a '78 hub to hub crossmember to get front disks but I haven't pulled the trigger for the booster and mc so I'm looking forward to your feedback on CP.

later,
Dan

[sandman]

Originally Posted by hedges

Sandman,
CP lists kit - 6366BBD as a drum/drum solution so they should be able to help. (I've seen their kits on ebay for less)

I have an Email in them (for almost a week now) about that very combination. I am attempting to find out if that works for 3/4T also.....my assumption is that it is 1/2T. I think the bores may be different. I have heard 1" for 1/2T and 1.25" for the 3/4T.

Since I have not recieved an answer, I will probably call them on the tech line. I want to see if, perhaps, they have made too much money lately and no longer have any room in their vault.

It also looks like they sell the booster, master clinder and proportioning valve seperately. The NAPA web site carries boosters but only single bore master cylinders for these trucks. Maybe they can xref the booster across years for you and recommend a later year mc that will work.

I have several Emails out to companies with those questions and have yet to get an answer. Oh, well, they are the folks who are trying to make money, not me... I am trying to spend some.

I've picked up a '78 hub to hub crossmember to get front disks but I haven't pulled the trigger for the booster and mc so I'm looking forward to your feedback on CP.

later,
Dan

I will be posting in here when I do the job, but right now am not too sure when that will be. I have a mother with Alz and has suddenly developed a tendency to wander... I need to get that taken care ASAP. I will keep an eye on what is going on in this thread.

Thanks for your feedback.