When I went to get a service kit, the guy asked if it had a sump tube. We couldn't find any way to determine. I ended up with two kits and will return one. I'll know when I get the pan off, but how to tell before hand?
I suppose it's safe to guess that you're doing a spill-n-fill or a flush on a 5R55E. In this case, the 4X models equipped with this tranny use a deeper pan, hold more fluid, and therefore require usage of a filter that reaches down lower into the pan than the 2WD model uses. This is how you tell before hand, and typically the parts catalogs found at stores that sell good quality, name brand filters (ex, WIX, Motorcraft) will indicate 2WD or 4WD next to the appropriate part number.