I have the white plastic (long and flat) surge tank in the engine compartment. It always looks empty. There is an “add” mark at the bottom, and a “full” mark towards the top. What does that mean? Should it be full when hot? Add when cold? Or hot? It’s almost impossible to tell from the engine access door because the thing is so opaque, you can’t see the fluid. Since I had the bed out and the top access cover open I was able to take the cap off. Sitting cold, there is a slight bit of fluid in the bottom. Below the add mark. Any ideas?
Thanks