What are all trucks with 4 tires on the rear axles required to have?

Trucks with four tires on the rear axles are required to have mud flaps or safety guards that reach within 8 inches of the ground to effectively minimize the amount of debris and water that gets kicked up from the tires. This requirement helps to ensure safer driving conditions for other vehicles on the road by reducing the risk of splash and spray that can impair visibility.

The specification regarding the height of these mud flaps or guards is important because it balances functionality with practicality. If the mud flaps are too high, they may not fulfill their purpose effectively. Conversely, if they are too low, they might not be durable enough to withstand road conditions or could be damaged easily.

The other options, which specify different measurements, either fall below or above the required standard. Hence, they do not meet the regulations set forth for safety equipment in trucks of this type. By being informed about the correct height of mud flaps or guards, drivers can ensure compliance with safety regulations and contribute to safer roadways.