This seems like a good point for my latest dumb question. How does one tell or what are the warning signs of a failing hydrovac system? I have fixed a couple large vacuum leaks in lines leading to the hydrovac. It is working, and the truck now stops with a noticeable "whooshing" sound from the air unit in the cab. Then there is a continued hissing noise while the brakes are held down. Is this normal? Or do I still have a leak somewhere? Right now, I am just testing the truck unloaded, but need to know that it can stop with when loaded.
