Our 5th wheel Toy Hauler is about 14k # when loaded up. The Truck is an '06 F-350 CC LB 6.0 with the OEM 20" Ford aluminum wheels and Goodyear Wrangler AT/s tires.

I know the 20" wheels are not the best for towing. Also I've had TWO wheels crack and TWO blowouts. I'm not pressing my luck any longer with these wheels and replacing with 18".
You can check out the cracked wheel post here....
https://www.ford-trucks.com/forums/1...l-cracked.html

The Goodyear AT/s are the OEM tire and I've always just replaced them. I'm on my 5th set in 175,000 miles. Time for a change as well. Haven't had good wear out of the Goodyears along with 2 front blowouts.

I was thinking of trying the Michelin LTX AT/2's E rated. They get high reviews. Just don't know how they handle towing heavy.

What are you haulers running?