Pn -SFRB99R1- Stainless Steel 1999-2003 F250 Cab Crew With Abs Rear Axle Brake Line Kit Made in the Usa. These lines typically run from the axle hose to each rear wheel which may have disc or drum brakes. Axle lines are usually come in twos and feed the rear brakes. They may go straight into the rear wheel cylinder or caliper or may have a rubber brake hose connecting the rear caliper to the metal hard line so when is time to change the pads, the caliper can be removed without disconnecting and rebleed the brakes. In many cases, axle lines have wrap on them to protect the line from road debris. adds protection to the line. Jeeps and trucks always have the and cars typically dont. Brake Lines are the metal hydraulic lines that carry the fluid that stops the car. If one line is bad the rest will typically soon fail. If replacing lines, is best to do all of them.