Slippage marks are required on tires that operate at a maximum of what psi?

Slippage marks are required on tires that operate at a maximum of what psi?

• A. Over 150 psi
• B. 150 psi or less
• C. All tires
• D. No limit

Answer: (B)

Slippage marks are visual indicators used to show whether a tire has moved on the wheel bead during operation or testing. They’re required on tires whose maximum operating pressure is 150 psi or less because lower-pressure tires are more prone to bead slippage under load. By applying marks on the tire and wheel, you can quickly see if there has been any relative movement after installation or a test run; if the marks stay in alignment, there’s no slip, and if they shift, it signals potential mounting or seating issues that need attention. Tires with higher maximum pressures are less likely to slip in this way, so the marks aren’t required there.

Slippage marks are visual indicators used to show whether a tire has moved on the wheel bead during operation or testing. They’re required on tires whose maximum operating pressure is 150 psi or less because lower-pressure tires are more prone to bead slippage under load. By applying marks on the tire and wheel, you can quickly see if there has been any relative movement after installation or a test run; if the marks stay in alignment, there’s no slip, and if they shift, it signals potential mounting or seating issues that need attention. Tires with higher maximum pressures are less likely to slip in this way, so the marks aren’t required there.