SHHHHH!
That's the one that usually gets burned up when the fluid is dark.
Keep in mind that the air going to both those clutches rely on steel rings kind of like a piston has to seal the air in as it passes through the to those clutchpacks.
Could that be how it sound not right?
When you put air to either clutchpack it should be a kind of definite "thunk" and maybe even a bit of a squawk sound on the rear clutch.