Power brake booster question
 

I'm no expert on brake compatibility so here's my question.

I have a 67 SWB 1/2 ton that does not have power brakes. I also have a 67 3/4 ton with power brakes. I was wondering if I could take the power brake booster out of the 3/4 ton and put it into the 1/2 ton, I would put a new master cylinder in it of course? If I can't do a straight up swap, is there any way to make this work?

Thanks in advance for any input,
Larry

Re: Power brake booster question
 

I see no reason why you can't do it. Not sure if you will actually need a NEW master cyl. though.

Re: Power brake booster question
 

The P/N for power and non power brakes for the master is the same. You'd need to keep the master that is on the 1/2 ton though, becouse the P/N for C/10 and C/20 are NOT the same. I think they have the resivours swapped front for back.

Re: Power brake booster question
 

should bolt right up just keep your master cylider

Re: Power brake booster question
 

Compare the pushrod (rod in between MC & booster) needed for your existing MC. Sometimes the depth needed is different, shallow vs deep. Very obvious difference. If they are the same, all that is needed to do is, pull the MC away from the firewall, bolt in the booster, then bolt the MC to the booster & hook up full-time vacuum.

Re: Power brake booster question
 

Thanks a lot guys, you've been very helpful. I didn't think that it would make a difference but sometimes when somebody is selling a booster people will ask if it is from a 1/2 ton, 3/4 ton, 1 ton, and so on. I always wondered why people asked that question. I guess I can kind of see why because if a 3/4 ton booster is rated for a heavier hauling load you probably wouldn't want to put in a booster rated for a 1/2 ton, for example. That is if that is a valid point of course, but I don't see the harm in putting a 3/4 ton booster in a 1/2 ton as long as it is compatible or could be made compatible.

Re: Power brake booster question
 

The 3/4 ton/one ton booster is a daul diafram unit, while the 1/2 ton is a single diafram piece. I don't know that I have ever driven a 1/2 ton with power assist, but I do know the booster on the 3/4 and one ton is a heck of a unit.

Re: Power brake booster question
 

I think it will work fine, too. You might have to mke some new lines, that dual diaphragm booster is pretty long. The difference in master cylinders between '67 1/2 tons and 3/4 tons is that the 1/2 ton has a 1" bore, and the 3/4 has a 1.125" bore. From the outside, the master cylinders look the same.

Re: Power brake booster question
 

You can do it with your existing lines. I put a 3/4 booster on my 70 and the only thing that wasn't long enough was the wire for the brake warning light. You get better braking with the 3/4 booster as a bonus.:D

Re: Power brake booster question
 

I even used a 1 ton unit on my 72. The bigger boosters give more assist than the stock 1/2 ton one does.

Like was said, there is plenty of slack in the lines to allow the booster without making new lines.

Re: Power brake booster question
 

It worked on mine....all I had to do was use my existing master cylinder and proportion valve. Now, when I get around to changing to front disk brakes, I'll have to change the ms & prop valve.