Chevy C-5500 Kodiak Duramax potential safety issue!

You should have power brakes for at least one or two actuations even with the engine stopped. If you didn't, then there's a problem with the brake system--the pressure accumulator (or associated valves etc.) if it's hydroboost braking, or the vacuum reservoir, etc. if vacuum powered, or the air tank if they're air brakes. I'd guess you probably have hyrdoboost brakes, but don't know for sure.

Hydraulic power steering, it is true, is unboosted pretty much immediately.