Yes, the Adco Olefin HD All-Climate + Wind RV Cover for 5th Wheel Toy Hauler # AD89ZR will work fine in north west Montana in the winter as this cover is designed to work in long term storage in all climates. view full answer...
It is indeed the valve stem that gives you the psi rating for the wheels, and if you'd like you can go to a bolt-in valve stem rated for over 100 psi, the Americana Metal, Bolt-In Valve Stem # AM20906.
You can use this valve stem along with a 16" x 6" wheel with a 6 on 5-1/2" bolt pattern to get its complete 3,050 capacity, the Dexstar Steel Mini Mod Trailer Wheel - 16" x 6" Rim - 6 on 5-1/2 - Silver Powder Coat # AM20746.
Then, since you want a 14-ply tire, you'd have to go with a load... view full answer...