Careful mixing the octane and blend names up...
88 octane E15 is cheaper than 87 octane E10 but your MPG will decrease slightly. The cost savings usually win out. The manual says we can use it. Do not use E85 or any other "E" greater than E15.
IAG is legit, I first came to know of them as a performance parts/engine builder for Subarus. Looks like they've expanded their offerings. The price of these steps are better than some of the few other offerings out there.
2023 JTR a couple months after I got it and was still fairly stock/unladen. Full tank of gas and no occupants:
Steer Axle 2720 lb
Drive Axle 2520 lb
Gross Weight 5240 lb (GVWR 6250 LB)
Don't forget the OP's diesel option adds 400 lbs and comes with a 6450 GVWR.
Glad to see this question pop up. The flap on my '23 is also on the outside, seems to pinch and offer little benefit when closing the door. Noticed when raining that flap really drops more water inside than even the usual annoying amount. The other frustration was watching the install videos to...
I'm going to guess the OP was looking more for the GAWR, which is on the driver's door jamb sticker. In that case a JTRD would be 3400 lb front and 3750 lb rear. As for Dana's rating, I'm curious in what application would allow use of a 22,000 lb weight rating?