I really don't know diddleysquat about tires - but here are my two cents .....
On our 09 Pathfinder we swapped out the "P" series tires that came with the truck. We found the OEM tires to be hard riding and terrible in the snow (a big deal for us). Our new tire criteria:
- first we wanted "LT" tires with a "D" load rating. I think most who tow would agree with both of these. Gives you a more robust tire with a stronger, more rigid, sidewall.
- second we wanted an all-season tire that could deal with our winters.
- and, of course, we were looking for longevity and driving comfort.
After spending some time with the folks at Fountain Tire we landed on M&S Goodyear Wranglers - LT 245 70R17 with load range E.
These tires were an all-season tire with a winter rating. They have a more aggressive tread design but not so aggressive that they create a lot of road noise. The tire size chosen was the closest in diameter to the tires we already had - my recollection is that they are a tiny fraction of an inch smaller. This particular tire did not come in a load range D - that was a bit of a concern for me at the time but in the long run has not been an issue at all.
These tires are finishing up their 3rd year on the truck - they've taken us through 3 winter and summer travel seasons - including our Alaska quest. When towing I use 42 psi and when not towing 38. The only complaint I have is that the tread design likes to pick up stones - and the front of the trailer does have a few "heritage" marks that it might not otherwise have - extended mud flaps are on my "new purchases" list for this spring.
Hope this is helpful - good luck with your purchase - and welcome to the Airstream family.