Sailun S637T Tires

The Sailun S637T is an all-steel radial trailer tire built for heavy and commercial trailer service. It is rated for trailer use only and must not be mounted on a passenger vehicle or light truck.

The all-steel casing is the whole reason to choose this over a standard polyester ST radial. Steel in both the sidewall and the tread raises load-carrying capacity, limits sidewall flex when the trailer is loaded to its rating, and produces a casing that runs measurably cooler over long distances. That directly addresses the failure mode heavy haulers actually experience, which is a heat-driven blowout on a hot highway with a fully loaded trailer, not a tire wearing out its tread.

A five-rib tread design provides essential straight-tracking stability behind the tow vehicle, preventing sway under heavy loads. Within those ribs, multi-sipes pull heat out of the contact patch and add wet grip, while wide grooves limit the stone retention that can eventually work through to the belts. A solid shoulder promotes even wear across the tread and keeps rolling resistance down, which matters on long commercial runs.

If you are stepping up from a polyester ST radial because you have had failures, the all-steel construction is the correct fix, but it only works if the rest is right. Match the load range to your trailer's loaded weight with headroom, inflate to the maximum pressure stamped on the sidewall before every trip and check it cold, and replace on age rather than tread depth. All-steel construction buys you margin. It does not make an underinflated or overloaded tire safe.

Best-suited for: Commercial trailers, gooseneck and equipment trailers, 5th wheels, horse trailers, heavy-duty cargo trailers, and large RVs.

Tire Best Features:

• All-steel casing maximizes load capacity and drastically reduces heat buildup compared to polyester tires.

• Five-rib tread design ensures straight-line tracking stability and confident towing under maximum payload.

• Solid shoulder construction resists irregular wear and lowers rolling resistance for long hauls.

• Multi-sipe design dissipates heat from the contact patch while improving wet-road traction.

• Wide grooves minimize stone retention to protect the steel belts from casing damage.

• Heavy-duty compound specifically formulated to resist cuts, chips, and abrasion on jobsites.