1977 Other GMC Models Can't find hydroboost hose

DRAGONBLUE24

MEMBER
1977 GMC
V8
2WD
MANUAL
89,000 MILES

Hello,

I bought an old GMC P3500 step van.
The first owner was a contractor and he ordered it with a heavy duty rear end and had disc brakes installed all around that have hydroboost.

Recently the line going from the power steering pump to the brake cylinder started leaking.
I removed the line but I had to cut one end to get it out since it was frozen to the pump.

I thought I could just go to the auto parts store and get a new one but no.

No one apparently has that line since it is not stock, GMC just shrugged their shoulders, the closest I found was a line for a G3500 van, length and fittings ok but the bends were different.
And the hose making places I went to weren't able to help either.

What can I do?

1 Reply

CARADIODOC

MECHANIC
33,916 POSTS

NAPA can make hoses, or try the heavy equipment shops if you haven't already. As long as you can get the correct fittings, you can make the bends in the steel lines. The typical pressure coming from the pump will be less than 1200 psi. The lowest grade bulk hydraulic hose is around 3-4,000 psi.

Depending on where the leak was and where you cut the hose, you might be able to reuse the old hose and fittings. Just cut the leaking section out and have the guys attach ends that can ce coupled together. Now that the corroded fitting is out, you can work it loose with a propane torch and penetrating oil, then clean it up with brake parts cleaner. Don't use too much heat as the rubber hose will melt in the crimp and pop out under pressure.

Caradiodoc