FREE CDL Combination Vehicles Practice Test Online | New Jersey 2024
Train for FREE online with our New Jersey CDL combination vehicle 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 NJ combination license in 2021, 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 DMV requirements for issuing a combination license may vary from state to state.
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1 . What does the trailer air supply control look like?
It is a circular orange knob.
On newer vehicles, the trailer air supply control is an eight-sided red knob. It's used to control the tractor protection valve.
2 . A tractor protection valve is:
A device that allows the battery to recharge efficiently.
On combination vehicles with air brakes, the tractor protection valve keeps air in the tractor or truck brake system, should the trailer develop a bad leak or break away from the tractor.
3 . Rollovers happen when:
You plan an escape route.
Rollovers happen as a result of drivers taking turns too fast.
4 . When traveling more slowly than 40 mph, maintain at least ____ of following distance per every 10 feet of your vehicle.
Four seconds
At speeds below 40 mph, you should allow at least one second of following distance for every 10 feet of your vehicle. Follow the same formula when traveling at faster speeds, then add one additional second to your following distance. Remember that larger vehicles require more space to stop than smaller vehicles.
5 . Which type of vehicle is most prone to the “crack-the-whip” effect?
A triple trailer
Triple combination trailers are most vulnerable to the "crack-the-whip" effect.
6 . What is a bobtail?
A tractor that goes slower than the speed limit
Tractors without semi-trailers are referred to as bobtail tractors. Operating a bobtail tractor requires drivers to exercise caution.
7 . When backing up to couple a trailer, you should position the tractor:
At a 60-degree angle in front of the trailer.
