6066 (1960-1966) GMC Truck Club

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- - My 64 GMC 1500 (https://6066gmcclub.com/showthread.php?t=49631)

Re: My 64 GMC 1500

cbeeker,

This is mostly in reply to issues James brought up. He makes a good point about reducing booster sensitivity. I don't really know how my booster was connected or who put it in (factory, dealer, or previous owner) because it was out before I started working on the pickup. But I haven't found any extra holes or bolts for connecting one. I have 4-wheel drum brakes, and the most weight I carry is a load of oak wood. When loaded, the rear brakes don't lock unless I push really hard, and I try to leave lots of space to stop. Use of dual cylinders and disc brakes in trucks came along at about the same time, so I would expect them to work better together, and the add-on systems I have seen use some sort of proportioning valve to regulate front and rear fluid flow, but I don't know how these work. In fact, I sort of gave up on learning new auto systems when points were replaced with computers and my timing light was replaced by more expensive equipment. I guess one reason I keep the old truck is that I can still work on it. My 2008 Dodge is much nicer to drive and the diesel engine pulls a lot more. But someone else fixes it.

jrmunn

Re: My 64 GMC 1500

Thanks for the communication. Agree driving my 2004 Tundra for daily use is the way to go. 64 GMC with Pullman Camper is just for fun use. But want it safe beyond single master cylinder. Ordering new shoes and wheel cylinders, and dual master to install before my next outing.

Charlie

Re: My 64 GMC 1500

cbeeker,

Good luck with dual cylinder. Installing cylinder was easy. I got one for first year GMC used it - and it fit. Problem for me was bending a line to fit under engine to get to fitting for line to back brakes. Then used plugs for front line. I don't remember why I went under engine except to get to other side where fitting was.

jrmunn

Re: My 64 GMC 1500

My brake lines run under the engine, was how the original line ran. I used a welding rod and bent it to make a pattern. I bend it around everything and make adjustment here and there then transfer it to the brake line.

Re: My 64 GMC 1500

Quote:

Originally Posted by jrmunn (Post 73350)

Cheeker,

I did not add a brake booster. The truck came with a vacuum boost that my father removed because it was too sensitive (but probably necessary to the first owner who carried a camper and found the 305E underpowered for the weight). I would be cautious about adding a booster if you don't need it for a load. My rear tires lock up on a moderate stop, even with the larger radial tires, and this could be dangerous with added brake power and sensitivity. On the other hand, I can still push hard on the brake pedal.

jrmunn

So, my plan is buy a dual master cylinder, and as you suggest- no booster. Seems the 67 Chevy C20 is first dual made. Any idea if this will match holes for my 64 GMC 3/4 ton?
Charlie

Re: My 64 GMC 1500

Quote:

Originally Posted by jrmunn (Post 73361)

Assume you refer to first year 67 GMC 3/4 ton???

Charlie

Re: My 64 GMC 1500

James,

Is that an aftermarket airco system, and are you going to repair it?

Re: My 64 GMC 1500

Quote:

Originally Posted by Prowbar (Post 73761)

James,

Is that an aftermarket airco system, and are you going to repair it?

Yes I am planning on getting it working again. Attached is the data plate of the John E. Mitchell Co. evaporator unit. When I got the truck there was no freon in it. Currently the York compressor been removed and planning on updating the compressor to something newer. Been working on other projects and I don't know when I will be able to get back to it (not high on my priority list).