Parked the truck facing uphill for the first time this week. It's a pretty steep hill and when the girlfriend went to move it, it just rolled backwards.

I investigated and found it was 1.5 quarts low in the transmission with a pretty decent puddle underneath.

Doesn't leak a drop when on level ground or with the nose down-hill.

I just briefly checked the pan and it didn't look like it was leaking (I recently put in a new Moroso pan gasket w/ RTV.) Where else would it leak from while on a hill? Tranny cooler and all of the lines are new and it seems like if it was the dipstick tube, then the opposite would be true and it would leak when facing downhill?