Florida CDL DMV Endorsement Double 2

A vehicle's total stopping distance is made up of perception distance, reaction distance, brake lag distance, and braking distance. With all of these factors included, an air brake-equipped vehicle traveling at a speed of 55 mph under ideal driving conditions will need approximately 450 feet to come to a complete stop.

To reduce the chances of becoming fatigued on a long trip, a driver should stop for a break at least once every two hours or 100 miles driven.

Most heavy-duty vehicles use dual air brake systems, in which there are two separate braking systems operated by a single set of controls. Each system operates the brakes on different axles.

Combination vehicles are usually heavier and longer than single commercial vehicles. For these reasons, they usually require more driving skill than single commercial vehicles.

It is always important to have enough water and antifreeze in a vehicle's cooling system. Despite the name, antifreeze is beneficial to an engine even in hot weather.

Always signal before a turn or lane change. Begin signaling well in advance of the movement and keep the signal on continuously during the turn. If it is not self-canceling, make sure to turn your signal off after your turn or lane change is complete.

Landing gear, or trailer supports, should always be completely raised before a vehicle is driven. When uncoupling, landing gear should be lowered to make firm contact with the ground. If a trailer is loaded when it is being uncoupled, you should lower the landing gear and turn the crank a few additional times to remove some weight from the trailer.

Always turn on your four-way emergency flashers if you must park on the side of the road. This is especially important when traveling at night.

Problems to check for when inspecting tires include: air pressure that is too low or too high; using radial and bias-ply tires together; tread depth of less than 4/32 of an inch in major grooves on front tires; and tread depth of less than 2/32 of an inch on all other tires.

Air brake system tanks must contain drain valves. These valves are used to drain accumulated oil and water from the tanks and may be either manually or automatically operated.

When stopping your CMV on the side of a highway, warning devices must be placed 10 feet, 100 feet, and 200 feet behind the vehicle.

To test the trailer service brakes, you should first ensure that the braking system has a normal air pressure level, then release the parking brake. You should then move the vehicle forward slowly and apply the brakes with the hand control. If the trailer service brakes are working properly, you will feel the brakes activate.

Black ice is a layer of ice that is thin and clear enough for the road to be visible through it. This makes the road look as if it is merely wet.

Before driving, you should always verify that your service brakes are in good working order. Testing the brakes before a trip allows you to locate any problems before you need to brake while on the road.

If you must drive in fog, you should use your low beam headlights and fog lights, even during the daytime.

On many vehicles, multi-speed rear axles and auxiliary transmissions are used to provide extra gears. They are usually controlled by a selector knob on the gearshift lever.

If your vehicle "pulls" to one side when braking, you may have brake trouble. If there is an issue with your brakes, you should fix the issue before driving. Operating an unsafe vehicle is against federal and state laws.

Because the weight of cargo gives them a higher center of gravity, fully-loaded rigs are 10 times more likely to roll over in a crash than empty rigs.

In adverse weather conditions, special care must be taken when driving a double or triple. They are especially prone to skids, loss of traction, and rollovers.

The majority of heavy-duty vehicles are equipped with dual air brake systems.