Knowledge Test Class B #1
Class B Driving Test | Texas 2026 #1 Page 5 of 7
Train for FREE online with our Texas class B license test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a TX CDL class B permit in 2026, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that CDL class B requirements may vary from state to state.
50
40
22
29 . If hydraulic brakes fail, a driver can reduce their speed by:
Letting the truck run out of gas.
If your hydraulic bakes fail, shifting into a lower gear can help slow your vehicle down.
30 . On trucks and buses, where are ABS malfunction lamps located?
Under the hood
Tractors, trucks, and buses with Anti-Lock Braking Systems (ABS) have yellow malfunction lamps located on their instrument panels. Trailers have yellow ABS malfunction lamps on their left side, either on the front or rear corner.
31 . Which of the following is an example of a serious traffic violation?
Traveling in a group of more than five CMVs
Serious traffic violations include excessive speeding (15 mph or more above the posted limit); reckless driving; improper or erratic lane changes; following a vehicle too closely; traffic offenses committed in a CMV in connection with fatal traffic accidents; driving a CMV without obtaining a CDL or having a CDL in the your possession; and driving a CMV without the proper CDL class and/or endorsements.
32 . The air entering air storage tanks may contain:
Antifreeze.
The air that enters air storage tanks in an air brake system usually contains a certain amount of water and compressor oil. Because accumulations of these materials can damage the braking system, tanks are equipped with drains to allow their removal.
33 . The parking brake should be:
Removed.
The parking brake in a vehicle with air brakes should be used every time the vehicle is parked.
34 . The air pressure in a dual air brake system should build from 85 to 100 psi within:
45 seconds.
When inspecting a vehicle with a dual air brake system, you should wait for air pressure to build from 85 to 100 psi in both the primary and secondary systems. This should take about 45 seconds.
35 . During the vehicle inspection test, you will be required to do all of the following, except:
Crawl under the vehicle.
