That's normal Matt. There have been some heated discussions in the past about it. Some swear by the dipstick others by the engineers who say 6 qts is all you need. I put 6 in mine and don't worry about it.
I work at Team Ford ( Las Vegas ) we put 7.3 qts , to the top of the stick. 04 to present 5.4 3V engines.
Wow thats significantly higher than recommended! i wouldn't recommend anything more than the 6 quarts, as too much oil can be just as bad as too little. the crank'll whip up the oil into a froth that the pump can't circulate and you still end up with oil starvation, especially in the heads.
I go by the dipstick, thats what it is there for. Mine takes around 7qts and has over 200K trouble free miles. A universally arbitrary number in a manual is not going to tell me what every single 5.4L's capacity is.
Here's something you will encounter with piston aviation engines. The dipsticks will show full at say 8 qts. So you change the oil and filter and top it off at 8 qts. A couple hours of flying and it's down to 6.5 and it will stay in the safe zone for many hours more. After a while you learn to just top it off at 6.5 instead of the 8 since the other quart and a half are blown out. Some engines are worse than others at this but they all function very well when not topped off with oil. If you sleep better with the dipstick reading full, ok. Your engine can't read the dipstick though and only knows when there is too much crankcase pressure or there is foaming from the crank splashing the oil.
One of the planes I fly will hold 12 qts but that would be a waste since it just blows it out. It runs very well at 9 and can be ran all the way down to 4. When the stick says it's at 8, I add a quart to make it 9.
Last edited by Ultramagdan; 02-10-2008 at 09:57 PM.