Falken Wildpeak A/T 3W
tires on my truck. I have found them to be great on dirt roads and wet pavement. Not enough snow this year to really know, but they are 3W rated ... so, I expect them to be "serviceable."
My truck came with LT275/65R18 with Load range of D from the factory. I later put on P275/65, which had a better ride, better MPG, but no more durability than the stock LTs. I wasn't towing, so no problems with the P -- well, occasionally a 3500 lb pop-up, but nothing big.
Earlier this year, knowing I'd be towing again, I went back to LT tires. I went with LT275/70 tires, which have a 1" taller stance. Load rating of E: 3,640 lbs at 80 psi. I lost nearly 2 MPG in economy going from the P to the heavy LT tires.
Ironically, Ford de-rates the tow capacity of the F150s with optional 18" wheels by 500 lbs against the standard model with 17" wheels ... but my tires are nearly 500 lbs each
greater in capacity than the 17" wheel equivalents. Very odd.