Hydroboost on a first gen?

[Ryan B.]

Anyone converted to hydroboost on their first gen k5?
I'm kinda thinking about going this route..
This weekend i went wheeling at hollister, and i was in a really hard spot, about to flop over and take damage between two trees when my brakes decided to intermitantly work. I think i was leaning so far over to the passanger side at one point that my master cylinder might have sucked air so thats why my brakes got crappy? i wouldn't think that is possible.. Somehow after 2 hours and throwing out my spare tire so i could drive the low side of my truck over it and not flop, i finally got out.
maybe my master cylinder is going out? once in a while it will be like there is almost no brakes.. then pump it up once or twice and theyre back.

 

[POWERMAD]

check this out

Scroll down to the last pic, it has been converted to hydraboost.
It may give ya an idea.

 

[crawford]

I converted mine to hyrdroboost.

It was pretty easy. It's alomst a bolt on. I had to drill a couple holes in the hydrobooster plate to mount it. The brake pedal had to have a hole drilled so it would connect to the hydrobooster. One of the fittings on the high presure hose had to be changed to the old style so it would connect to the steering box. That's about all the hangups I ran into.

Works great now. I can lock all four tires up really easy.

 

[Yukon Jack]

I reinforced the firewall as they hydroboost setup is pretty heavy. Here is a pic of the firewall and how the rod is attached to the brake pedal.

I also had to have one of the hoses modified to use the old style fitting at the steering box.

For the short period that the truck drove before the engine problem, sure seemed to work great.

 

[uglytruck]

Last month I installed a hydroboost out of an old k30 into my 72k5 and it is way better than the stock set up. I can actually lock up my 35" bfg's on any surface now . I had always wanted to do it but I didn't really need it. Higher priorities. Without warning my master cylinder went out on the trail and prompted the conversion. By the grace of God it happened at a place where I didn't need my brakes and I was able to make it home with out incident.
Please don't trust your master cylinder another foot. I would recommend hydroboost or I have also heard that the vacuum booster and master cylinder out of 3/4 and 1 ton trucks help increase braking. I also installed heavy duty 3/4 ton calipers. I needed to grind into the webbing a little to allow for clearance but the original mounting holes are the same. With that order the heavy 3/4 ton pads as they are larger.
Very soon I plan on upgrading to stainless steel flex lines as I'm not entirely comfortable trusting increased brake pressure in 33 year old brake lines. I hope this helps, I can give specifics and many part #s if you need. Good luck!

 

[Ryan B.]

Thanks for the replies...
Yah i junked my old master cylinder and replaced it the day after i got back from hollister... Totally fixed my problem.
I also started that post a few years ago about the 3/4 ton power booster... it works awsome and made night and day difference in my braking.