CDL Class B Pre Trip Inspection Practice Exam 2026 - Free CDL Practice Questions and Study Guide

The air pressure in tires should be checked using a tire pressure gauge. This tool provides an accurate measurement of the air pressure within the tire, ensuring that it is within the manufacturer's recommended specifications. Proper tire pressure is critical for safety and performance, as it affects vehicle handling, fuel efficiency, and tire wear.

Using a handheld air pump may inflate a tire, but it does not provide a precise measure of the current pressure, making it ineffective for checking if the tire is at the proper level. Listening for leaks is insufficient as it does not give a quantitative readout of the pressure and could lead to underestimating or overestimating tire conditions. Visual inspections can identify obvious issues such as bulges or tread wear but cannot determine whether the tire is properly inflated. Therefore, utilizing a tire pressure gauge is the most reliable and essential method for accurately checking tire pressure.