Ontario MTO Truck Knowledge Practice Test

Tread depth on the rear tire must not be less than:

1. 5 centimeters

2. 2.5 inches

3. 3 millimeters

4. 1.5 millimeters

The correct answer is: 1.5 millimeters

The correct answer is that the tread depth on the rear tire must not be less than 1.5 millimeters. This minimum tread depth is crucial for maintaining adequate traction and handling, especially in wet or slippery conditions. A sufficient tread depth helps to channel water away from the tire, reducing the risk of hydroplaning and ensuring that the vehicle can grip the road effectively. Having a tread depth greater than 1.5 millimeters also contributes to better stability and performance. It is vital for safety regulations that require tires to meet these specific standards to ensure vehicles operate safely on highways and roads. The other options represent tread depths that are higher than what is legally required, which may not reflect the actual safety standards set by transportation authorities. Therefore, they do not meet the regulatory needs while maintaining an effective balance between safety and performance on the road.