I will be putting on my "D" rated GY endurance tires today. I'm a little late to the party. Just read about this a few days ago. My trailer has OEM "C" rated tires on it from the factory, same as you, the load rating was just about at max on the OEM tires. Glad I caught this before our 1,000 mile trip to the coast in a few weeks!It had C rated tires when I bought it, which are 1820 lbs each. I bought and had D rated tires at 2149 lbs each. I felt like the C rated were going to just barely be adequate if I ever have the trailer loaded to its max gvwr and one corner is heavy. My trailer axles are almost a perfect 50/50 split.
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