Classes of Tire Chains

The Society of Automotive Engineers (SAE) has established three classes of tire chains, each with different clearance requirements.

• SAE Class S: This class is applied to regular (non-reinforced) tire chains and cables for vehicles with restricted wheel well clearances. It has a minimum tread face clearance of 1.46 inches (37 millimeters) and a minimum side wall clearance of 0.59 inches (15 millimeters).
• SAE Class U: This class is applied to regular (non-reinforced) and lug reinforced tire chains and cables for vehicles with regular (non-restricted) wheel well clearances. It has a minimum tread face clearance of 1.97 inches (50 millimeters) and a minimum side wall clearance of 0.91 inches (23 millimeters).
• SAE Class W: This class is applied to passenger tire chains that use some light truck grade components, as well as some light truck chains. It has a minimum tread face clearance of 2.5 inches (63.5 millimeters) and a minimum side wall clearance of 1.5 inches (38.1 millimeters).

When choosing tire chains, it is important to make sure that they have the correct clearance for your vehicle. If the tire chains do not have enough clearance, they could damage your vehicle.

To measure the clearance for your vehicle, you will need to measure the distance from the tread face of your tire to the nearest obstruction, such as the wheel well or suspension components. You will also need to measure the distance from the sidewall of your tire to the nearest obstruction.

Once you have measured the clearance, you can use the SAE clearance chart to determine which class of tire chains is appropriate for your vehicle.

It is important to note that the SAE clearance requirements are minimum requirements. Some vehicles may require more clearance than the SAE minimum. It is always best to consult your vehicle owner's manual for specific clearance requirements.

Here are some tips for using tire chains:

• Only use tire chains when necessary. Tire chains can damage your vehicle if they are used on dry or wet roads.
• Install tire chains before driving in snow or ice. It is difficult to install tire chains while driving.
• Drive slowly and carefully when using tire chains. Tire chains can reduce your vehicle's speed and handling.
• Remove tire chains when you are no longer driving in snow or ice. Leaving tire chains on your vehicle can damage your tires and suspension components.