Preguntas CDL de Vehículos Combinados gratis

Preguntas de ejemplo de este examen

1. About how many truck driver deaths in crashes are caused by rollovers?¿Aproximadamente cuántas muertes de camioneros en choques son por volcaduras?
   1. About one in ten
   2. About one quarter
   3. More than half
   4. Almost none
   Ver respuesta

   More than half

   More than half of truck driver crash deaths result from rollovers.

   Más de la mitad de las muertes de camioneros en choques son por volcaduras.

2. You make a sudden turn while pulling doubles. Which trailer is most likely to tip over?Si gira de golpe jalando dobles, ¿qué remolque es más probable que se vuelque?
   1. The first trailer
   2. The rear (last) trailer
   3. Both equally
   4. Neither; only the tractor tips
   Ver respuesta

   The rear (last) trailer

   Because of rearward amplification, the last trailer is the most likely to turn over.

   Por la amplificación trasera, el último remolque es el que más probablemente se vuelca.

3. Which trailer is most likely to get stuck (hung up) on a raised railroad crossing?¿Qué remolque es más probable que se atore en un cruce de tren elevado?
   1. A dry van with normal ground clearance
   2. A lowboy
   3. A flatbed with high clearance
   4. A tank trailer with tandem axles set correctly
   Ver respuesta

   A lowboy

   Low-slung units like lowboys, car carriers, moving vans and possum-belly livestock trailers can hang up.

   Las unidades bajas como lowboy, portaautos, mudanzas y possum-belly pueden atorarse.

4. Once the trailer swings out of your lane in a skid:Cuando el remolque ya salió de su carril en un derrape:
   1. It is easy to correct with the hand valve
   2. It is very difficult to prevent a jackknife
   3. ABS will always straighten it
   4. You should accelerate hard
   Ver respuesta

   It is very difficult to prevent a jackknife

   Once the trailer leaves your lane, a jackknife is very hard to prevent, so catch it early in the mirrors.

   Una vez fuera del carril, la tijera es muy difícil de evitar; detéctelo temprano.

5. While backing, the trailer starts to drift off the proper path. How do you correct it?Al retroceder, el remolque se desvía del camino. ¿Cómo corrige?
   1. Pull the trailer hand valve
   2. Stop and set the parking brake for 1 minute
   3. Turn the top of the wheel away from the drift
   4. Turn the top of the steering wheel toward the drift
   Ver respuesta

   Turn the top of the steering wheel toward the drift

   Fix drift right away: turn the top of the steering wheel toward the side the trailer is drifting to.

   Corrija de inmediato girando la parte superior del volante hacia la desviación.

6. The tractor protection valve closes automatically when air pressure drops to about:La válvula protectora se cierra sola cuando la presión baja a aproximadamente:
   1. 60 to 80 psi
   2. 100 to 125 psi
   3. 20 to 45 psi
   4. 5 to 10 psi
   Ver respuesta

   20 to 45 psi

   It closes automatically when pressure is low, in the 20 to 45 psi range.

   Se cierra sola con presión baja, en el rango de 20 a 45 psi.

7. The service line connects to relay valves. What do relay valves do?La línea de servicio se conecta a válvulas relevadoras. ¿Qué hacen?
   1. Release the spring brakes
   2. Let the trailer brakes apply more quickly
   3. Fill the tractor tanks
   4. Close the tractor protection valve
   Ver respuesta

   Let the trailer brakes apply more quickly

   Relay valves allow the trailer brakes to be applied faster than would otherwise be possible.

   Las válvulas relevadoras aplican los frenos del remolque más rápido.

8. With an older trailer without spring brakes, crossed air lines and an empty trailer tank, what is the danger?Con un remolque viejo sin frenos de resorte, líneas cruzadas y tanque vacío, ¿cuál es el peligro?
   1. The trailer will not move at all
   2. You could drive away with no trailer brakes
   3. The tractor brakes will lock
   4. The fifth wheel will unlock
   Ver respuesta

   You could drive away with no trailer brakes

   Without spring brakes and with no tank air, the wheels turn freely, so you could drive off with no trailer brakes.

   Sin frenos de resorte y sin aire, las ruedas giran libres y podría arrancar sin frenos.

9. Why should you use wheel chocks when parking a trailer without spring brakes?¿Por qué usar calzas al estacionar un remolque sin frenos de resorte?
   1. Chocks are required only on hills
   2. The air in the trailer tank will eventually leak away and the brakes will release
   3. Chocks keep the ABS working
   4. The fifth wheel may unlock
   Ver respuesta

   The air in the trailer tank will eventually leak away and the brakes will release

   Emergency brakes on these trailers hold only while there is tank air; when it leaks away, there are no brakes.

   Los frenos de emergencia solo aguantan mientras hay aire; cuando se escapa, no hay frenos.

10. Which statement about ABS is correct?¿Qué afirmación sobre el ABS es correcta?
    1. It increases your normal braking power
    2. It always shortens stopping distance
    3. It helps you keep control during hard braking
    4. It works all the time, even in gentle stops
    Ver respuesta

    It helps you keep control during hard braking

    ABS doesn't necessarily shorten stopping distance, but it helps you keep control in hard braking.

    El ABS no necesariamente acorta la distancia, pero ayuda a mantener el control.

11. What can happen if the fifth wheel plate is not kept greased?¿Qué puede pasar si la placa de la quinta rueda no está engrasada?
    1. The trailer will be too low
    2. The ABS will fail
    3. Friction can cause steering problems
    4. The air lines will cross
    Ver respuesta

    Friction can cause steering problems

    Without lubrication, friction between tractor and trailer can cause steering problems.

    Sin grasa, la fricción entre tractor y remolque puede causar problemas de dirección.

12. How do you check that the trailer is locked onto the tractor (step 11)?¿Cómo comprueba que el remolque quedó enganchado (paso 11)?
    1. Look at the ABS lamp
    2. Push the trailer air supply knob in
    3. Raise the landing gear slightly and pull forward gently with the trailer brakes locked
    4. Back up hard against the kingpin
    Ver respuesta

    Raise the landing gear slightly and pull forward gently with the trailer brakes locked

    With landing gear slightly off the ground, pull gently forward against the locked trailer brakes.

    Con el landing gear un poco arriba, jale suave contra los frenos trabados.

13. After the landing gear is up and the trailer weight is on the tractor, what clearance must you check?Con el landing gear arriba y el peso en el tractor, ¿qué espacio debe revisar?
    1. Between the glad hands and the cab
    2. Between the trailer roof and bridges
    3. Between the rear of the tractor frame and the landing gear
    4. Between the mud flaps and the ground
    Ver respuesta

    Between the rear of the tractor frame and the landing gear

    Check clearance between the tractor frame and landing gear (for sharp turns) and between tractor tires and the trailer nose.

    Revise el espacio entre chasis y landing gear y entre las llantas del tractor y la nariz.

14. When you inspect the coupling from under the trailer, where should the fifth wheel locking lever and safety latch be?Al revisar el acople desde debajo del remolque, ¿cómo deben estar la palanca de cierre y el seguro de la quinta rueda?
    1. Lever in "open," latch hanging free
    2. Lever in "open," latch removed
    3. Lever halfway, latch beside it
    4. Lever in "lock," safety latch over the lever
    Ver respuesta

    Lever in "lock," safety latch over the lever

    The locking lever must be in the "lock" position with the safety latch in place over it. On some fifth wheels you must set the latch by hand.

    La palanca debe estar en "lock" y el seguro colocado sobre ella. En algunas quintas ruedas el seguro se pone a mano.

15. When uncoupling a gooseneck hitch, after removing the safety pin and clip, what is next?Al desenganchar un gooseneck, después de quitar el pasador y el clip, ¿qué sigue?
    1. Lower the trailer jacks onto the truck bed
    2. Disconnect the air lines
    3. Drive forward with the trailer still on the ball
    4. Rotate the handle to release and raise the trailer off the ball
    Ver respuesta

    Rotate the handle to release and raise the trailer off the ball

    Rotate the handle and raise the trailer off the ball; the coupler returns to load position automatically. Then reinstall the pin and clip.

    Gire la manija y levante el remolque de la bola; luego vuelva a poner el pasador.