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Rusted brake line repair

I need to repair some rusted thru brake lines in the rear of my 96 Intrepid. I assume I can’t get the line any longer so I will have to buy stock brake lines and bend it as best I can. Also I assume the stock stuff needs the gas tank dropped to install and no way am I doing that. What brand of brake line is best for bending? I have done some internet research and some brands claim they can be easily bent by hand with out kinking. I am looking for the easiest way out so if I have to pay up for better materials I will. Also I plan to flair each end inspite of others telling me to use compressions fittings. I don’t know that they can be trusted on a brake line. Any comments appreciated.

You probably can get the line. Have you checked?

You can buy a tubing bender for about $5.

You may be able to run a new line without dropping the tank. have you looked carefully?

I too prefer flared endings.

Tubing benders are dirt cheap, as are brake lines which are stocked at any decent auto parts store. If you are really fortunate, you may be able to buy a stock length that will match up to your existing connectors after whatever bending is needed.

You’re right that flared fittings are said to be preferable to compression fittings, but if you are trying to graft a section into an existing brake line, you may find that you simply can’t get a satisfactory flare into the existing lines. In that case, you may have to use compression fittings.

You can practice your flaring on the section that you cut out. If you can’t flare the tubing properly at your workbench your chances of flaring it properly on a stub still attached to the car while slithering around on your back are close to zero.

You don’t want use compression fittings in brake lines. At the most, a compression fitting is only good to 10,000 PSI. A hydraulic brake system can see pressures as high as 30,000 PSI.

When replacing a brake line, go to your local parts store and purchase various lengths of stick brake line, some flare fitting couplers, and a tube bender. Start at the proportioning valve and disconnect the bad brake line and all the clips under the vehicle. When enough of the brake line is freed that the longest stick can replace it, cut it off. Now take that part of the old brake line, and with the tube bender, shape the new line to match as close as possible to the old. Connect the new line to the proportioning valve losely. Now locate the flexible line at the rear axle and remove the bad brake line. Again with tube bender and the proper length of new line as before. fashion the new brake line. If there’s areas where a full stick can’t be used, then use shorter sticks to form the brake line. When all the new brake line is installed, use the flare couplers to connect them. The return the lengths of brake line/couplers you didn’t use to the parts store for a refund.


Do not use compression fittings, dangerous and maybe illegal. You will not be able to buy prebent from the dealer so go to the parts store to purchase and get a tube bender.

Steel, pre-flared brake lines are available in MANY different lengths. Don’t try to splice brake lines with compression fittings. You will find the tubing is sized to prevent the use of compression fittings. The new lines can be formed to fit with little trouble…

Thanks to all who replied. I never felt good about using a compression fitting and now I am convinced.

One of my questions was about the type of replacement line to purchase. Elderman makes a product called EasyFlex. They say it can be bent by hand with out kinking. But…They don’t provide a minimum bend radius. I have all of the tools to bend and flair and have some experience doing it on my back. Some of the bends radii are pretty tight. Some areas it bends around have close quarters so it has to match pretty closely. I see it being a potential problem with matching the OEM exact enough.
Is this EasyFlex product realy worth searching out?

Thanks again.

One way to make tight radius bends is to fill the line with sand. This prevents kinking of the line. Then before installing the line, clean it out with compressed air.


Brake lines are usually too small and too long for the sand method…It is not necessary to match the OEM bends exactly. As long as the connections are correct and the lines properly secured to the chassis of the car. Replacement lines are usually pretty easy to form without kinking problems…If your replacement is a little to long, you can form a loop to shorten it.

Great idea. Similar to what cars use to do at the master cylinder. Any idea of how tight a radius I can safely bend?

A loop is a great idea. Loops in sealed lines are commonly used as “stress reliefs” anyway. They allow movement of the ends relative to one another as well as movement due to things like thermal expansion and vibration without stressing the connections.

I think those numbers may be KiloPascal (kPa) rather than PSI. The conversion factor is 6.9. I’m pretty sure that if you managed to apply 30000psi (15 tons per square inch) to an automotive braking system, you’d likely be picking pieces of brake hose and brake lines out of the garage walls for weeks. And even then, I’m a bit skeptical about the maximum pressure. Some manufacturers seem to consider 20000 kPa (3000psi) to be an adequate test pressure for brake lines and tubes. (But don’t some ABS systems pump up above 2500psi?)

I’m not real sure about any of this.