I posted the tread about looking for parts for a 48 ford fire truck. We were looking it over today and noticed that on of the hard brake lines going to the right rear wheel is completely snapped. I know on air brakes if the line brakes the brakes will lock up. Could this be causeing the rear brakes to be locked up on the truck?

 

That only happens on air brakes as air pressure is used to release the brakes from the spring pressure. Most likely it`s been sitting too long and the shoes are rusted to the drums.

 

Hydraulic brakes are the opposite - a broken line means you have NO brakes.