How to Replace the Brake Lines in a '98 Sonoma

When replacing a brake line, it is important to consult with an auto parts dealer to ensure that you get replacement brake lines designed for your 1998 GMC Sonoma truck. New metal lines designed for the truck will already be bent in the shape you need in addition to being flared with the fittings installed. This will to make it easier to install a new line. The process is much like replacing a metal brake line on any other vehicle.

Instructions

1

Raise the Sonoma truck on the front or rear end--the end with the leaking, corroded or otherwise damaged brake line--and support that end on at least two jack stands. Remove the wheel for the corresponding brake line.

2

Clean away all dirt and dust from the brake line fittings using a rag and compressed air.

3

Loosen and disconnect the brake line fitting at the hose end near the wheel first and then at the other end; apply penetrating oil to the fittings if they are excessively rusted. Plug the open end at the chassis with a rubber plug.

4

Insert the replacement line into its brackets on the frame and make sure that there is clearance between the metal line and any hot or moving parts. Twist the new line's fittings into place and tighten the fittings with your wrench.

5

Connect a clear tube to the bleeder valve--the screw-like valve at the top of the brake caliper--and place the tube's other end into a small container partially filled with brake fluid.

6

Open the valve while another person pushes on the brake pedal; fluid and air should come out of the tube into the container. Close the valve and repeat until fluid flows out the tube with no air.

7

Reconnect the wheel and lower the truck off of the jack stands.