Oklahoma CDL DMV Endorsement Tank 1

If you must drive so slowly that you will impede the flow of traffic, you should turn on your four-way flashers to alert drivers behind you (as long as local laws allow the use of flashers).

If you remain in neutral for too long while switching gears, you may have difficulty putting the vehicle into the next gear. If this happens, do not try to force the gear shift. Instead, return to neutral, release the clutch, increase the engine speed to match the road speed, and try again.

In the event of an engine fire, turn off the engine as soon as possible. Do not open the hood if you can avoid doing so.

When driving, you should frequently check the mirrors on both sides of your vehicle.

Tractors without semi-trailers are referred to as bobtail tractors. Operating a bobtail tractor requires drivers to exercise caution.

You should be cautious when you are near people who are not paying attention to the road. Drivers and pedestrians who are talking to someone may be distracted by the conversation and not fully paying attention to the road. Workers on or near the road may not be paying attention to traffic because they are focused on their work, and can themselves also be a distraction to drivers.

Hazardous materials warning placards are usually diamond-shaped.

The trailer hand valve (also referred to as the "trolley valve" or "Johnson bar") works the trailer brakes and should be used only when testing them. Using the trailer hand valve while driving could result in a skid.

While swerving can sometimes be the safest way to handle a hazard on the roadway, doing so is not without risk. Top-heavy vehicles and tractors with multiple trailers may flip over in a swerve.

During a pre-trip inspection, be sure to check the mirrors and windshield for dirt and anything else that could interfere with your ability to see. Clean them as necessary.

Your vehicle's stopping distance can be calculated by adding together your perception distance, your reaction distance, and your vehicle's braking distance. Reaction distance is the distance traveled between the moment you mentally perceive a hazard and the moment you physically hit the brakes.

During a pre-trip inspection, you should check for emergency equipment, including spare electrical fuses; three red reflective triangles, six fuses, or three liquid burning flares; and at least one properly charged and rated fire extinguisher.

The force of gravity will cause a vehicle's speed to increase when traveling downhill.

All trailers and converter dollies manufactured on or after March 1, 1998 must have Anti-Lock Braking Systems (ABS).

Always change lanes slowly and smoothly. If you did not see drivers who are already using the lane you wish to occupy, this will give them a chance to get out of your way or honk their horns to alert you. Always signal when changing lanes.

At speeds below 40 mph, you should allow at least one second of following distance for every 10 feet of your vehicle. When traveling at higher speeds, follow the same formula, then add one additional second to your following distance.

The suspension system holds up a vehicle and its load while keeping the axles in place. Defects in this system are extremely dangerous.

Always signal before turning or changing lanes to ensure that other drivers are aware of your intentions.

Tires should never have too much air pressure. Be sure to check your tires' air pressure with a gauge during inspections.

Your truck may block the views of drivers behind you, making them unaware of any upcoming hazards that require you to stop. For this reason, it is a good idea to flash your brakes and warn other drivers before slowing or stopping.