By Ken Freund
Like many other trailer owners, I have had many problems with the made-in-China Nanking ST225 75R15D tires that came with our less-than-four-year-old trailer. According to my research, these are the important things to do.
Load range weight: Weight pickup and fifth-wheel trailer often (there's a scale four miles from our house). Our trailer is rated for 9,700 pounds. We've always been under that, weighing in at 2,000 pounds on the hitch and under 7,500 pounds on two trailer axles.
Tire pressure: Monitor often and keep correct 63-65 psi (measure when cold). I also purchased a Doran Pressure Pro for our tires, and am very happy with it. It continuously monitors the tire pressure, and lets me know if a tire is losing pressure so I can pull off before the tire is destroyed and causes major problems.
Speed: Our usual travel speed is 58 to 62 mph, a very few short durations up to 65 mph.
Alignment: I took our trailer in for alignment, and they said it didn't need an alignment. They also thought my tires were bad. Subsequently, I had two more tread separations.
I read on the Internet that going from a D load range to an E tire could make our wheels split. Is there any truth in that? Is there any advantage to going to an E LR over a D with our trailer weight? From what I've read, a light truck tire can safely replace an ST tire as long as it has the proper load rating. Have you found this to be correct? While the ST tires also are supposed to have more UV protection, our trailer is garaged except when we're using it, which is mostly in the winter.
I've considered going to a 16-inch wheel, allowing us to buy Michelin tires so that we'd have a reliable tire. However, it would cost us over $1,000 for the tires and wheels, and also add weight to our trailer. From our research, it seems that most of the ST tires are made in China, and I haven't read anything good about them. How can we know that we're getting a truly reliable tire? We have not been able to find a made-in-America, 15-inch load range D or E tires, and only an ST tire in load range D is a Goodyear Marathon (and the reviews for them aren't great). I found ratings for passenger tires, but little for ST tires.
Thank you for help figuring out which tires to purchase.
Ken Settlemier
Good Sam Member
Response:
Yes, truck tires will work. Many RVers use them and they sound like the solution for you, especially if you don't keep the rig out in the weather and sun all the time.
The wheels shouldn't split going from D to E unless you exceed the wheel's design air pressure or weight-limit rating.
Ken Freund
Good Sam Club