Question 1

Technician A says there may be three drive shafts connected to a transfer case. Technician B says one drive shaft is connected to the transfer case, directly from the transmission, and the other two are for driving the front and rear axles. Who is correct?

Accepted Answer

Both technicians are correct. Technician A is correct in stating there may be three drive shafts connected to a transfer case, and Technician B is correct in detailing the configuration: one from the transmission and two for the front and rear axles.

Question 2

Part-time four-wheel drive systems are automatically controlled systems.

Accepted Answer

Part-time four-wheel drive systems require the driver to manually switch between two-wheel and four-wheel drive modes; they are not automatically controlled.

Question 3

The _____, often referred to as the interaxle differential, allows the front and rear wheels to turn at different speeds and with different amounts of torque.

Accepted Answer

The center differential is the correct answer as it specifically allows the front and rear wheels to turn at different speeds and with different amounts of torque, which is the function described in the question. The other choices (open differential, rear differential, front differential) may be found in a vehicle's drivetrain but do not specifically match the function described in the question.

Question 4

Full-time four-wheel drive _____.

Accepted Answer

Full-time four-wheel drive is always engaged and cannot be manually disconnected, hence it is never disconnected.

Question 5

Four-wheel-drive is most useful when a vehicle is traveling off the road or on any slippery surface.

Accepted Answer

Four-wheel-drive provides better traction and stability on slippery surfaces such as mud, snow or gravel, which makes it useful for off-road driving or in harsh weather conditions.

Question 6

Technician A says a transfer case is an extra gear box on the back of a transmission. Technician B says a transfer case is mounted between the engine and the transmission. Who is correct?

Accepted Answer

A transfer case is not mounted between the engine and the transmission. It is an additional gearbox that is connected to the transmission and sends power to both the front and rear axles. Therefore technician A is correct, and technician B is incorrect.

Question 7

Although the principles of operation are similar for all 4WD units, the components, location, and controls of the various systems differ primarily according to _____.

Accepted Answer

The components, location, and controls of 4WD systems differ primarily according to the manufacturer and application, as different manufacturers may use different components and controls based on their own design preferences and the intended use of the vehicle. Car make and model, body style, and engine specifications may also play a role, but they are typically secondary factors that are influenced by the manufacturer and application.

Question 8

Most transfer cases, with low range available, use planetary gearsets.

Accepted Answer

Most transfer cases with low range use planetary gearsets because of their ability to provide high torque output and compact design.

Question 9

Some vehicles may be shifted into four-wheel drive at any time.

Accepted Answer

Some vehicles have the ability to shift into four-wheel drive at any time, while others may require the vehicle to be stopped or in neutral before engaging four-wheel drive. It's important to consult the owner's manual or seek guidance from a professional to understand the appropriate way to engage four-wheel drive in your specific vehicle.

Question 10

A locking hub is a type of clutch that engages the outer ends of the axle shafts from the wheel hub.

Accepted Answer

The answer of A locking hub is a type of...

Question 11

All-wheel-drive systems give the driver the option of 2WD or 4WD.

Accepted Answer

All-wheel-drive systems automatically distribute power to all four wheels, and do not have the option of only using two-wheel drive.

Question 12

The Society of Automotive Engineers (SAE) provides standard definitions applicable to AWD and 4WD systems which is used consistently by manufacturers to provide clarity.

Accepted Answer

The answer of The Society of Automotive Engineers (SAE) provides...

Question 13

Technician A says the purpose of a transfer case is to transfer power to an additional drive axle. Technician B says most transfer cases have two speeds which affect the overall gear ratio of the vehicle. Who is correct?

Accepted Answer

Technician A is partially correct. The purpose of a transfer case is to transfer power to both front and rear drive axles, not just an additional drive axle.

Technician B is correct. Most transfer cases have two speeds (high and low), which affect the overall gear ratio of the vehicle. The low range gear ratio is used for off-road, slow-speed driving, while the high range gear ratio is used for normal driving conditions.

Question 14

The outer case of the transfer case is made of magnesium, aluminum, or cast iron and is filled with lubricant.

Accepted Answer

The outer case of the transfer case is typically made of magnesium, aluminum, or cast iron and is filled with lubricant to protect the internal gears and components.

Question 15

Part-time four-wheel drive _____.

Accepted Answer

Part-time four-wheel drive is usually disconnected when driving on pavement to prevent damage to the drivetrain. It is typically controlled by a lever or button in the vehicle that the driver can use to switch between two-wheel drive and four-wheel drive modes.

Question 16

Both 4WD and AWD systems add cost and weight to a vehicle.

Accepted Answer

Both systems require additional components and heavier materials, which contribute to increased cost and weight in a vehicle.

Question 17

A viscous clutch, cone clutch, or a multiple-plate clutch are three types of clutches that may be used in a(n) _____ differential.

Accepted Answer

A limited-slip center differential can send power to both the front and rear axles in varying amounts, depending on the traction available. To achieve this, a viscous clutch, cone clutch, or multiple-plate clutch can be used to transfer torque from one axle to another. In an open differential, torque is transferred to the wheel with the least amount of traction, while a closed differential sends an equal amount of torque to both wheels. However, neither is capable of sending power to the opposite axle. Therefore, the limited-slip center differential is the best choice for off-road vehicles or those driving in slippery conditions.

Question 18

The _____ has the role of recommending specifications and practices for the automotive industry.

Accepted Answer

The Society of Automotive Engineers (SAE) is an organization that recommends specifications and practices for the automotive industry. Neither shop owners union nor shop employees union have a national role in the automotive industry. While manufacturers may provide specifications for their own vehicles, they do not play a general role in recommending practices for the industry as a whole.

Question 19

A 4WD vehicle may be shifted into four-wheel drive _____.

Accepted Answer

The correct operation for shifting a 4WD vehicle into four-wheel drive varies by vehicle and is specified in the owner's manual, making it essential to follow the manufacturer's instructions.

Question 20

Most transfer cases use drive chains.

Accepted Answer

Most transfer cases use drive chains to transfer power between the transmission and the front and rear axles.

Quiz 8: Four Wheel Drive Systems Servicing Four-Wheel Drive Systems