From an Airstream forum Post:
"Yes, there is a definite difference between Cooper LT and ST tires.
However, it is not a "safety" difference as long as the load rating is correct for your trailer's gross weight when towed. Both ST and LT tires can be safely used for trailers. The difference in construction is this: Cooper ST tires are basically a tire that combines passenger car
tire construction techniques, with heavy duty truck tire fabric and cord materials. This results in an ST tire having a high LT type load rating with the lower air pressure requirements and soft, shock absorbing sidewalls of a passenger tire. There is also extra UV inhibitors and oils added to the rubber to help in storage. This is much easier on the suspension and other components of the trailer on bumpy roads than the stiff sidewalls and higher air pressure of the LT tires. As far as tire safety is concerned, he stated that is up to the owner and how he maintains the tires, keeping the proper air pressure in the tires, and choosing the correct load rating. He stated LT tires have an advantage because of the larger choice of tread patterns and number of sizes available to choose from to suit the conditions you are towing in, such as snow, unimproved roads, etc. He also stated that it is imperative to not allow the trailer to rest on the tires in the same spot for months at a time in the off-season. This causes the fabric cords in the tire to take on a flat "set" which can then cause some of them to actually break apart when you next take the trailer out on the highway. This can cause complete tire failure. He stated the best thing to do is to store the trailer on jacks with the tires in the air, or removed completely. This last information was of concern to me since I only have "stabilizing" jacks and cannot lift the trailer enough to take the load off the tires without serious effort. At any rate, that is what Cooper Tires has to say on this subject."
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Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
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