Dave, I consider the GY 614s on a loaded Landmark to be marginal. Many folks say they can be expected to last about three years if properly aligned, inflated and loaded. I plan to replace my axles with 8k rated with disc brakes, and replace the GY614s with 17.5" wheels and tires. Not cheap, but no more than the damage the factory installed stuff can do.
I don't mean to criticize Heartland over any other mfr; but I like a better safety margin than the rv industry feels it needs to be competitive.
I don't mean to criticize Heartland over any other mfr; but I like a better safety margin than the rv industry feels it needs to be competitive.