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Brake line cut per mechanic. foul play or normal wear and tear?

The brakes failed on my 2002 Subaru Impreza Outback Sport when I was driving home from work the other night. Fortunately for me it was late and no one else on the road and I was only a couple miles from home and drove it safely back to my house. I thought it might be a master cylinder that failed or something which might be expected on a car with 178000 miles on it like mine has. I talked to the mechanic this morning who told me that the brake line had been “cut” and I asked him if it might have been done by someone maliciously and he said he could not say that for sure and it did not look like a clean cut as if with a knife. Just wondering if this has happened to others and what was your conclusion that you arrived at?

We’d have to see a picture to make any sort of guess, and even then it can be difficult to tell the difference between a brake line that was torn by a flung rock and a brake line that was torn by a rock wielded by an attempted murderer.

A 200,000 mile, 15 year old car is not an unusual candidate for failed flex lines, so unless you think you’ve got someone angry with you, and you think that someone is the type to want to kill you over it, it’s probably just a failed part.


Your wife has not mentioned lately anything about raising your life insurance. Maybe you forgot her birthday!!!

Up here in the rust belt in Wisconsin, it is very common for the hard brake lines to rust and then break on any vehicle over 10 years and maybe sooner. Seems to me the leaks are almost always at a point where the line is held to the frame rail by some method.
I currently am working on a 2001 F150 that blew a line. Lucky for the owner he was right at the property where my shop was. We just nursed the truck into the shop. All I had time to do was to cut off the line and remove the section from a point near where the firewall meets the floor pan to the rear flex line fitting. You could snap that old line easily anywhere it was badly rusted.

I always replace these with teflon coated lines.

I have also seen newer lines that had been snapped in two by road debris. So I wouldn’t worry too much about someone maliciously cutting a brake line.


Has there been any work done on the wheel where the hose failed? If the caliper is pulled off its mount it must be supported to prevent damaging the rubber hose. Allowing the caliper to hang on the hose will often damage the hose and the damage may not result in failure for several weeks.

Never had anyone cut my brake line but had a union guy threaten to get his gun. Those things are flexing all the time and are exposed to the elements. Cracks develop before they fail so. Even if one failed, you still have brakes on two wheels. Guess unless you’ve been threatened, it just wore out so have the other three changed at the same time since they have to bleed the system anyway.

Brake lines are steel.

Brake hoses are rubber.

It’s impossible to cut a brake line with a knife.

Do you mean a brake hose?


Determining why something failed is a tricky business. Your use of quotes around the use of “cut” by the mechanic tells me you are skeptical of the analysis. Unless you have other evidence likewise, attribute it to bad luck or mechanical failure or a little carelessness on some previous brake work and move on with your life.

as a matter of fact I had the tires rotated about a month ago. I have the car back now and it is repaired and driving well again and the old brake line does not have a sharp cut in it as the clerk had said but the place where it leaked through a pin hole looks as if it had been rubbing against something and I am not sure what. The other thing that still bothers me also is why I never noticed a break warning light come on on the dash. The light works when the emergency brake is engaged but I never saw it when the brake fluid was low. I am wondering if there is a sensor in the master cylinder for that and the master cylinder may have still had fluid in it somehow and the brakes still failed.

Could be the brake fluid reservoir float hung up and didn’t trip the sensor.

Brake fluid reservoirs are large enough to supply fluid to the system to actuate the brakes 10 to 20 times when there is a leak.