How to Flare Brake Lines with the S.U.R.&R. Pistol-Grip Flaring Tool

How to Flare Brake Lines with the SURR Flaring Tool

A pistol-grip flaring brake line tool adds a flare to the end of your vehicle’s brake lines to ensure the connection will not leak. Though most brake lines are pre-flared, cutting and splicing damaged sections of brake line or building your own custom brake line replacements may require you to use a flaring tool to flare a brake line at one or both ends in order to fit your vehicle. Getting high-quality brake line flares can be tricky to do yourself, so be sure to have enough time, focus and resources so you can avoid a leaking brake line repair. A pistol-grip flaring tool is among the easiest ways to get professional-quality brake line flares quickly and consistently. If you don’t feel comfortable performing this repair yourself, the Parts Professionals at your local O’Reilly Auto Parts store would be happy to recommend a trusted repair shop in your area. Our detailed, step-by-step instructions will help you perform brake line flaring to your vehicle’s brakes quickly and easily using a pistol-grip flaring tool.


Additional Resources

Show More Show Less

Tools & Materials

safety glasses Safety Glasses
Protective Gloves Nitrile Gloves
S.U.R.&R. Pistol Grip Flaring Tool S.U.R.&R. Pistol Grip Flaring Tool

Flaring Brake Lines Instructions

This flaring tool is simple to use, and it’s designed to give you consistent, quality flares on brake lines either on or off your vehicle. Just make sure the line is evenly cut and deburred before starting the process. This tool will work for lines of 3/16, ¼, 5/16 and 3/8 inches, as well as 4.75mm lines. If you’re not completely comfortable doing this yourself, we’d be happy to recommend a professional technician in your area.
Show More Show Less

Prepare Your Vehicle

Cutting the brake line

Step 1: Cut the Brake Line

Before flaring your brake line, make sure it has been cut square and deburred.
Show More Show Less
Align the Die Sets

Step 2: Align the Die Sets

Use the pins to align the die set and then put them together.
Show More Show Less
Place the die in the yoke

Step 3: Place the Brake Line in the Yoke

Place the brake line in the yoke. The yoke is magnetic, so it should secure the dies when they’re properly seated. Slide the brake line in until its end is flush with the inside port.
Show More Show Less
Secure the brake line

Step 4: Secure the Brake Line

Then, tighten the clamp to secure the brake line in place.
Show More Show Less
Punch on Front Flaring Tool

Step 5: Choose the Appropriate Punch

Choose the appropriate punch for the flare you need, and put it in place against the detent ball at the front of the pistol.
Show More Show Less
Pump the Brake Line

Step 6: Pump the Flaring Tool

Now, snap the pistol into the clamp and pump the handle several times until it is snug.

Do It Right: The pistol features crimping pressure of six thousand pounds per square inch, so there’s no need to squeeze beyond the point where it is tight.

Show More Show Less
Punch on Front Flaring Tool

Step 7: Change the Punch

Swap out the punch on the front of the pistol in order to invert the flare.
Show More Show Less
Reinsert the pistol

Step 8: Invert the Flare

Reinsert the pistol into the clamp with the new punch and pump the handle like before.
Show More Show Less
Brake line finished product

Step 9: Release the Clamp and Ensure Proper Flare

Now, release the pistol from the clamp, loosen the clamp, and slip the dies and brake line out. Check your flare to make sure it looks perfect.
Show More Show Less

Additional Resources

Braking System Basics

Braking System Basics
Change Brake Pads and Rotors

How to Install Brake Pads & Rotors
bleeding brakes

How to Bleed Brakes

These step-by-step instructions and video detail how to use a S.U.R.&R. pistol-grip brake line flaring tool to perform brake line flaring without hassle. If you are performing a brake line replacement, or building new brake lines, you will likely need to modify the brake line to fit your vehicle, which is why it’s important to know how to use a pistol-grip brake line flaring tool. Using the flaring tool is a straightforward, precise procedure that can help you avoid a brake line leak. Our easy-to-follow instructions can teach you to use a pistol-grip flaring tool to help you make brake line flares that are leak-free, consistent, and easy.

Show More Show Less

The automotive repair work depicted in this series is performed under the direction of the manufacturer of the product featured. Prior to undertaking any of the demonstrated repairs on your vehicle, we suggest you consult with a certified mechanic or another professional who can adequately advise you of the proper repair or remedy required. O’Reilly Automotive Stores, Inc. and its affiliates (“O’Reilly”) disclaims any responsibility for injury or damage resulting from a viewer’s attempt to recreate the repairs shown in this series.