I noticed that the manual for my 2016 F150 suggests using synthetic dif oil if towing frequently near the max tow rating or in hot weather. I assume that means that the drug did not come with synthetic fluid which is dissappointing since I purchased the max payload package. Since I am towing heavy I plan to do that soon along with putting a different cover on with drainplug and cooling fins. I feel that the truck should have come with everything recommended in the manual for what it was obviously purchased to do.