Exam 126: Four-Wheel-Drive and All-Wheel Drive

Two technicians are discussing the towing of a four-wheel-drive vehicle. Technician A says that the vehicle should be transported on a flatbed truck to avoid the possibility of doing damage to the drive train. Technician B says that the wheels not lifted off the ground by the tow truck should be placed on a dolly to prevent doing damage to the drive train. Which technician is correct?

A transfer case contains all of the following components, EXCEPT ________.

The planetary gearsets used in transfer cases consist of all of the following components EXCEPT ________.

Technician A says that a vehicle equipped with part-time four-wheel drive should be driven in four-wheel drive only on slippery surfaces. Technician B says that full-time four-wheel-drive vehicles use a center differential in the transfer case. Which technician is correct?

A transfer case is difficult to shift (range shift). Technician A says that the shift linkage or shift fork may be worn or damaged. Technician B says that the blocking ring may be worn or damaged. Which technician is correct?

Two technicians are discussing the purpose of a transfer case in a four-wheel-drive system. Technician A says it transfers power to an additional axle. Technician B says some transfer cases have two speeds. Which technician is correct?

Two technicians are discussing the viscous coupling used in all-wheel drive systems. Technician A says a viscous fluid such as a silicon-based oil is added to the assembly and fills the areas between the clutch plates. Technician B says the viscous coupling is active during equal traction conditions. Which technician is correct?

A customer complained of excessive vibration while cornering and accelerating at the same time. Technician A says that a fault in the transfer case is the most likely cause. Technician B says that the vibration may be normal if the vehicle is equipped with Cardan U-joints at the front wheels. Which technician is correct?

Two technicians are discussing the front axle disconnect mechanism. Technician A says that the front axles are only disconnected if the vehicle is being towed. Technician B says that this unit is only used on All-wheel-drive vehicles. Which technician is correct?

Technician A says some 4WD vehicles use a solid front axle. Technician B says some 4WD vehicles use halfshafts to send torque to the front wheels. Which technician is correct?

Technician A says some front 4WD hubs must be manually locked and unlocked. Technician B says some front 4WD hubs can be automatically locked and unlocked. Which technician is correct?

Technician A says that most transfer cases have a built in oil pump. Technician B says that most transfer cases use a heavy grease as a lubricant. Which technician is correct?

What 4 wheel drive system is shown in this drawing of a front axle?

Technician A says a 4WD transfer case is an auxiliary 2-speed transmission. Technician B says a planetary gearset provides a low and high range. Which technician is correct?

Driveline wind-up on a part-time 4WD system results in all of the listed conditions EXCEPT ________.

Technician A says that the gear ratios of both differentials are the same in a four-wheel-drive vehicle.Technician B says that the rear differential has a slightly higher ratio (lower number) than the front differential. Which technician is correct?

When part-time 4WD vehicles in 4WD are engaged in a turn, which of these occur?

Which component is used in some transfer cases to prevent driveline windup?

Technician A says that a transfer case may use GL-4 gear lube such as SAE 80W-90. Technician B says that a transfer case may use automatic transmission fluid (ATF) such as Dexron III. Which technician is correct?

Technician A says full time 4WD also allows the driver to select 2WD or 4WD. Technician B says part-time 4WD includes a differential or viscous coupling that allows the front and rear axles to rotate at different speeds. Which technician is correct?