I haven't been under my daughter's '02 GMC Envoy 4.2L 4x4 to change the transmission fluid yet, however when I went to get the parts (gasket and filter) the parts guy says "deep pan or shallow pan". I had to go outside to make sure I didn't accidentally go to the pizza place, but no...this is the Advance Auto Parts place. So how does one tell the diff? He says "well the shallow pan is a little shallower" welllll....what do I say to that without risking a pop to my schnozz? I was planning on doing this work this afternoon but I hate to buy both. Uless the best strategy is to buy both and return the one I don't use. So is there any way to tell before I jack the thing up and crawl under it to know which part I need?