I'm always short on time, so condensing both units into one thread. I'm not sure, but I believe that the transfer case is probably the factory fill. The rear diff lube report looks too low on iron to be the factory fill, although it came out grey colored, which is what some others have reported when draining the factory fill on F150s. So.... 
Sorry, but uncertain of what we're looking at here. I bought the truck earlier this year with 81k miles and while it's in great condition, I don't know the service history.
Odometer read 91k miles when these samples were taken. I refilled the rear diff with M1 75W-140 and for the transfer case, I used Valvoline Transfer Case Fluid. The Valvoline TC fluid is said to cover Ford's XL-12, GM Auto Trak II and ATF+4 applications.
Cat SOS reports, tested by Milton Cat in Massachusetts.
The transfer case wasn't full before I pulled the plug. I stuck my pinky finger in and could barely touch the fluid. After putting in 1.5 quarts (listed capacity), the new fluid was close to running out of the fill hole. This is my first time testing the TC fluid in any of my pickups, so I don't know if my results are as bad as I think, but "yikes!" is what comes to mind.
Guys and gals, check your factory fill fluids. Don't assume that they get it right when assembling a new vehicle. 
Sorry, but uncertain of what we're looking at here. I bought the truck earlier this year with 81k miles and while it's in great condition, I don't know the service history.
Odometer read 91k miles when these samples were taken. I refilled the rear diff with M1 75W-140 and for the transfer case, I used Valvoline Transfer Case Fluid. The Valvoline TC fluid is said to cover Ford's XL-12, GM Auto Trak II and ATF+4 applications.
Cat SOS reports, tested by Milton Cat in Massachusetts.
Code:
Ford 9.75" rear diff Borg Warner TC 3.55 with electronic locker (electronic shift on the fly) 75W-140 (unknown brand, miles) uncertain, but probably factory fill Odometer 91k miles 91k miles Copper 1 40 Iron 333 603 Chromium 2 1 Aluminum 1 39 Lead 0 2 Tin 1 1 Silicon 22 61 Sodium 2 11 Potassium 4 9 Boron 52 25 Moly 1 0 Nickel 25 16 Silver 0 0 Titanium 21 1 Calcium 8 84 Magnesium 1 82 Zinc 14 24 Phosphorus 1134 82 Barium 0 3 Oxidation 61% 11 Nitration 4% 4 Sulfation 64% 19 Visc @ 100C 24.5 5.2 PQI 59 89 ISO 23/23/21 22/20/16 4 micron 50248 38039 6 micron 40489 8495 10 micron 24638 1064 14 micron 12816 438 18 micron 4264 212 21 micron 1444 129 38 micron 382 36 50 micron 287 23
gets to drive a semi. No need to compensate.
Your transfer case UOAs looked fantastic on your 2010 FX4, mine is a little scary to look at. Hopefully, mine will go on to live a long life with proper care. I will consider switching to Amsoil in my TC next year, but I'm going to send in a sample of the Valvoline TC fluid for VOA and give it a workout this winter. I will see how it looks next spring.
That's fine. I'll tell you what came to mind...my friends saw the 75W-140 on the shelf in my garage, waiting to go in the rear diff. They (Chevy guys) laughed and said if I needed that heavy of lube, I should just get a heavier duty truck. Their trucks use 75W-90 so it seemed silly that I would be using the heavier grade. I've seen similar sentiment in some F-150 threads where guys wondered why Ford was using 75W-140. I thought maybe you were looking at it like that.