I've put several hundred thousand miles on Goodyear Wrangler Silent Armors, 99% of that was towing, and they were good tires. I don't know if they make them in the size you want, but if they do you might take a look at them. They're pretty quiet and well mannered on the road, handle well in the wet, and are pretty decent off road (more of an AT tread design).
We would get around 40k out of a set, but they were never rotated and there was always a trailer on the back. At that point the rears were getting worn out but the fronts still had quite a few miles left in them, I would estimate that you should be able to hit 60k miles with proper rotation.
This was on a 6.0 Diesel Excursion, '04 F-350 Diesel, '08 F-250 Diesel, and an '08 GM 3500 Duramax. We had a few sliced sidewalls (but never through the entire sidewall), but other than that they were pretty durable and always got us where we needed to go, on or off road.
We would get around 40k out of a set, but they were never rotated and there was always a trailer on the back. At that point the rears were getting worn out but the fronts still had quite a few miles left in them, I would estimate that you should be able to hit 60k miles with proper rotation.
This was on a 6.0 Diesel Excursion, '04 F-350 Diesel, '08 F-250 Diesel, and an '08 GM 3500 Duramax. We had a few sliced sidewalls (but never through the entire sidewall), but other than that they were pretty durable and always got us where we needed to go, on or off road.