Why Is A Double Flare Use On Brake Lines?

If you’ve never worked on your car’s brakes before, you might be thinking: “What is a flare?” “What is a double flare?” “What does a flare have to do with the brake system anyway?” If you’re not a mechanic, the lingo might completely miss you, as this kind of technical jargon is not heard commonly when you hear laymen referring to brake jobs.

So do brake lines need to be double flared? Double flares are necessary for brake lines due to the high pressures inflicted on them by the hydraulic system. Single flared lines are only appropriate for low-pressure lines due to their tendency to crack or leak. The brake system cannot afford to have a leak in the lines since this can cause serious injury or death if the brakes fail.

What is the difference between single flared lines and double flared lines in a vehicle, and how do they affect your brake system? Read on to find out more about double flared brake lines and why they’re so important when fixing your brakes.

Single Flared Lines vs. Double Flared Lines

While some single flared lines may show up on cars that have been incorrectly repaired by a shade tree mechanic, a double flared line is the OEM standard for automotive braking systems and, as such, is a much safer option in the brake system to avoid any kinds of leaks or other pressure-related issues.

Here are some of the various flared lines you might see in your car’s braking system:

  • Single flared lines: While you might run into single flared lines in an automotive design elsewhere, you should never see them in the brake system unless someone has gone into repair the brake system and not put it back together correctly. Single flared fittings should never be used on steel brake lines.
  • Double flared lines (SAE): These are the type of brake line fittings that are most commonly found in American and Asian models of vehicles. Double flared lines help control friction wear and cracking at the sight of the flare that can ultimately lead to a leak in the line.
  • Bubble flared lines (DIN): These line fittings are more common in European models but are considered equal in safety to a double flared line when they are used in high-pressure systems on a vehicle.

It might cost you a bit more on the front end to invest in a flaring tool that can create double flared fittings for your brake system, but it’s a whole lot less expensive and complicated than trying to recover from a catastrophic brake failure while you’re out on the road. Give us a call at Chapman Auto Repair if you have more questions!