Hi I am looking into purchasing a 1985 pick up and was wondering about the brake light being on. The man I am buying it from says that when the light comes on he adds brake fluid to the truck and it fixes the light. This is telling me that it is leaking somewhere. I have heard that it may be the master cylinder leaking or it could just be somewhere in the lines. If it is the master cylinder leaking what would be somethings that I should look for? If it makes a difference the truck is 2WD. Any and all information on this would be greatly appreciated.

 

as far as master cylinder leaking, check where the cylinder mounts to the vacuum booster. might even unbolt it from booster and check for fluid. check for leaks around calipers up front and pull wheels off rear to check for wheel cylinders leaking. also, check all lines and fittings.

 

Check the 4 wheels carefully. If brake fluid gets on the brake pads or shoes, it will greatly reduce your breaking.

 

Thank you for your help I will double check the truck this has helped quite a bit.