
A Banjo bolt is a hollowed-out bolt typically used in hydraulic brake systems. Its name comes from the coupler’s banjo-like shape. But don’t let a funny name fool you, the Banjo bolt is much more than a fastener.
Banjo bolts serve three important functions.
- They fasten brake lines to other critical brake components – typically used to attach brake lines to other critical hydraulic brake system hardware.
- They create a high-pressure seal – brakes can run 1500 psi plus under braking, and the banjo bolt together with the banjo fitting and sealing washers help keep all that pressure where it’s needed…..at the brake pads.
- They become part of the fluid circuit – the banjo bolt cavity allows for fluid flow and becomes part of the fluid circuit
Where’s Banjo Bolt Located?

A banjo bolt may be found in high-pressure fluid circuits such as fuel and power steering systems, but in a brake system, banjo bolts are typically found at brake calipers and at brake couplers.
That said, banjo bolts aren’t widely used in the latest automotive brake systems.
You may find the following links helpful:
- About the Author
- Latest Posts
John Cunningham is an Automotive Technician and writer on Rustyautos.com. He’s been a mechanic for over twenty-five years and has worked for GM, Volvo, Volkswagen, Land Rover, and Jaguar dealerships.
John uses his know-how and experience to write articles that help fellow gearheads with all aspects of vehicle ownership, including maintenance, repair, and troubleshooting.