You should be able to find the oil capacity on google or even on this site somewhere. My bus takes 5 gallons with a filter change. The AT545 transmission takes about 5 gallons of fluid with the normal pan on it if you change the filter out, but this could vary by as much as a quart depending on how much drainback occurs due to wear, how many external filters you have, etc. As far as coolant goes, I've never fully drained my system. I do know that 1 inch low in the radiator means 2 full gallons low though.