I am finally back to replacing the hydraulic brake line hoses on my 1966 GMC HM5500 truck. It looks like Raybestos makes reasonably priced hoses for the front wheels, but I have another question about the rear brakes hose. Both Raybestos and Bendix catalogs specify two hoses in the back. I only have one hose that goes from a 1/4 inch steel line (originating at the hydrovac) to a splitter that sends 3/16 inch steel lines along the back of the axel to each rear wheel. This single rear hose and its fittings have a total length of 24 inches, and I can't find it in a catalog.
So I have been trying to get the rear hose made. But all of the places I have gone, including truck shops, only carry hydraulic brake line hose with about a 1/8 inch diameter hole and similarly small inlet tubes in the fittings. This seems to be very small compared to the diameter of steel lines that the hose is connecting to, and it must carry the fluid needed for operating brakes on both rear wheels, each of which have two cylinders per wheel. I know that brakes work because of the fluid pressure, but it still seems that the hose needs to move enough fluid to expand four, large wheel cylinders to the point where pressure is applied.
Is this small hose hole size a real problem, or am I just imagining things? Any information about hydraulic brake hose sizes for old medium duty trucks would be greatly appreciated. And if I need a larger diameter hole, I am looking for suggestions about where to get the hose made. Thanks, again, for any help and advice.
