PSI
Trailer says 50psi, tires say 65psi, tire store says 5 less than max which is 60psi. Who is right?
Forum Discussion
PSI is not a difficult concept to work with. Use it to your advantage......or not.
"This bulletin provides important information to help your customers obtain the best performance from “Special Trailer” tires. Please review the following important points with your trailer tire customers. Special Trailer (“ST”) Tires: Goodyear Marathon trailer tires are widely used in a variety of towable trailer applications and are designed and branded as “ST” (Special Trailer) tires. Industry standards dictate that tires with the ST designation are speed rated at 65 MPH (104 km/h) under normal inflation and load conditions. Based on these industry standards, if tires with the ST designation are used at speeds between 66 and 75 mph (106 km/h and 121 km/h), it is necessary to increase the cold inflation pressure by 10 psi (69 kPa) above the recommended pressure for the rated maximum load."
"This bulletin provides important information to help your customers obtain the best performance from “Special Trailer” tires. Please review the following important points with your trailer tire customers. Special Trailer (“ST”) Tires: Goodyear Marathon trailer tires are widely used in a variety of towable trailer applications and are designed and branded as “ST” (Special Trailer) tires. Industry standards dictate that tires with the ST designation are speed rated at 65 MPH (104 km/h) under normal inflation and load conditions. Based on these industry standards, if tires with the ST designation are used at speeds between 66 and 75 mph (106 km/h and 121 km/h), it is necessary to increase the cold inflation pressure by 10 psi (69 kPa) above the recommended pressure for the rated maximum load."
