Front brake hoses; nothing is simple

Most people don't realize that when they push on the brake pedal, the pressure in the brake system can spike as high as 1000 psi. The lines in the car are made of steel, or a metallic alloy, to handle this pressure. Brake hoses are flexible links between the brake hard (metallic) lines on the car and the individual wheels. They are necessary because of the movement of the suspension. The disc brake kit we installed includes new hoses. Of course these are for a later model application than the 1958 stockers. And of course they don't just bolt on without some modification.

Here is another look at a stock hose. For all I know, they could be original, making them 54 years old. I have seen brake lines go bad in 10 years. Without even looking closely, you can see major cracking of the outer material. Trust me that brake lines crack internally way before they crack externally. Internal cracks cause flaps of material to block the passageway, leading to uneven brake pressure. This causes a car to pull to one side under braking. When both fronts have this problem, the car will dodge left and right under braking. It's a pretty scary feeling, and I hope you never experience it.

It's hard to see here, but I'm using the pointy ends of my dial caliper to measure the brake hose anchoring hole in the frame. On the '58 the hole is a consistent diameter.

The new hose ends have a unique shape where they fit into the frame, sort of an elongated oval with two flats on the ends. These fit into similarly shaped holes in the frame of whatever car they are designed to fit; this is still a common configuration. The idea is that you can wrench on the hard line fitting without the hose spinning since it is keyed and cannot rotate.

Here I am measuring the rough width of the oval part of the fitting. If this was a constant diameter it would slip right into the frame hole.

Just to confirm the diameter I need I measured the old hose end.

The eternal question is; do I grind the hose ends into diameters to fit the frame, or do I file the new hose end profile into the frame tabs? Normally I don't like to modify parts, because a later replacement will not just bolt on in the field if need be. Of couse you know I don't like to modify the car either, because it is the original 54-year old item. In this case I decided to modify the hoses for two reasons. One, it is far easier to modify the hose ends than the car, and two, I don't expect these hoses to need replacement anytime soon, since they will lead a well-cared for life.


I have the hose secured in a vise. I put a piece of tape over the end to keep grinding dust out. The horseshoe-shaped clip is just a stop that keeps the hose end from slipping too far through the frame hole. It goes in the slot you see. I spread it and removed it to get better access to the hose end.

Here I have my trusty angle grinder at the ready. We're going to grind the top part, above the groove. I ground the angles off and made this top land into a rough circle, going just by eye.

Somehow I have no pic of the finished work, but as I said I was just going for a rough circular shape. This is one case where exactness is not required, it just has to be the right size to fit nicely into the hole. That's what she said.


Here is the original hose anchoring clip. Be careful not to lose this since the new hose doesn't include a replacement. You know how much I dig reusing the original anyway, right?

Incidentally these get installed top-side up as shown. They should put enough pressure on the hose end to keep it firmly in place. If you're doing it right, it should take some taps from a hammer to install. If you have it upside-down, it will virtually slip into place by hand, but will not keep the hose secure and probably just fall off. I like to add a smear of grease to these to ease installation and keep corrosion at bay.


At last, our new hose end is securely in place on the frame. Our nemesis, Mr. Looped-Brake-Line is photo-bombing us, upper right, but it's a desperate measure; his days are numbered, and he knows it.

If you look closely, you can see the horse-shoe clip is the bottom stop, and our original securing clip is topside. The final reason I knew I could modify the hose ends is the flats that are evident just below the horse-shoe clip. I can still put a wrench on these to keep the hose from rotating during brake line tightening or removal.

Just front brake hoses, yet nothing is simple.