Question 1

Which of the following statements about sidewall markings is true?

Accepted Answer

The tire's sidewall markings include the maximum safe inflation pressure and the maximum load the tire can carry. This information is crucial for maintaining proper tire inflation and ensuring vehicle safety.

Question 2

Technician A says an incorrect tire and wheel size can affect bearing life. Technician B says changing tire and wheel sizes does not affect antilock brake systems. Who is correct?

Accepted Answer

Technician A is correct because incorrect tire and wheel sizes can indeed affect the load and alignment on the bearings, potentially leading to premature failure. Technician B is incorrect because changing tire and wheel sizes can affect the antilock brake system (ABS) by altering the wheel speed sensor readings, which the ABS uses to determine braking actions.

Question 3

Technician A says the front-wheel bearings on a typical FWD car are pressed in and out of the steering knuckle. Technician B says the rear-wheel bearings on a typical FWD car are often serviced in the same way as the front-wheel bearings for an RWD car. Who is correct?

Accepted Answer

Technician A is correct because in many front-wheel drive (FWD) vehicles, the front-wheel bearings are indeed pressed into the steering knuckle, requiring a press to remove and install them. Technician B is also correct because the rear-wheel bearings on a typical FWD car are often designed similarly to those on rear-wheel drive (RWD) vehicles, where the bearings can either be pressed into the hub or serviced as a hub assembly, making both statements true.

Question 4

A tire that wobbles from side to side is said to have ______.

Accepted Answer

Lateral runout refers to the side-to-side wobble or deviation of a tire or wheel from its true rotation axis. This can cause vibrations and uneven tire wear.

Question 5

Technician A says tire traction ratings are indicated with an A, B, or C. Technician B says tire temperature ratings are indicated with an A, B, or C. Who is correct?

Accepted Answer

Both Technician A and Technician B are correct. Tire traction ratings, which indicate a tire's ability to stop on wet pavement, are indeed indicated with an A, B, or C rating. Similarly, tire temperature ratings, which reflect a tire's ability to withstand heat, are also indicated with an A, B, or C rating.

Question 6

Which of the following statements is NOT correct?

Accepted Answer

Wheel balancing is not only required when new tires are installed but also in other situations, such as after a tire repair or if there is uneven tire wear. It helps ensure the tire rotates smoothly, preventing vibrations and premature tire wear.

Question 7

Which of the following materials is not used in the body and belts of radial tires?

Accepted Answer

Copper mesh is not used in the body and belts of radial tires. Steel mesh, nylon, and fiberglass are common materials for reinforcing the structure of radial tires, providing strength and flexibility. Copper mesh, however, is not used in this application due to its properties and cost.

Question 8

Technician A says that front-bearing assembly locknuts for RWD vehicles are heavily torqued to maintain the bearing adjustment. Technician B says that the axle nut for a FWD front-wheel bearing assembly is often staked in place. Who is correct?

Accepted Answer

Technician B is correct because the axle nut for a FWD front-wheel bearing assembly is often staked in place to prevent it from loosening. Technician A is incorrect because front-bearing assembly locknuts for RWD vehicles are not heavily torqued; they are typically adjusted to a specific preload and then secured with a cotter pin or similar device.

Question 9

Which of the following statements is false?

Accepted Answer

The bead in a tire is not a decorative pattern; it is actually the part of the tire that ensures a tight fit against the wheel rim, providing the seal that holds the air in the tire. It is made of steel wires that are coated in rubber.

Question 10

On a tire with a designation of P205/70R14, the distance between the rim and the top of the tire is ______.

Accepted Answer

The distance between the rim and the top of the tire, known as the aspect ratio, is represented by the number following the slash in a tire designation. In this case, it's 70% of the tire's width (205 mm), which calculates to 70% of 205 mm.

Question 11

Technician A says many modern vehicles are equipped with bias ply or belted-bias ply tires. Technician B says modern vehicles are equipped with radial ply tires. Who is correct?

Accepted Answer

Modern vehicles are predominantly equipped with radial ply tires due to their superior durability, fuel efficiency, and performance compared to bias ply or belted-bias ply tires.

Question 12

Most information about a car's tires can be found ______.

Accepted Answer

The tire placard, usually located on the door edge, doorpost, glove box door, or fuel door, provides information about the car's tire sizes, pressures, and load capacity.

Question 13

Why are aluminum wheels superior to stamped steel wheels?

Accepted Answer

Their lower unsprung weight improves handling.

Question 14

Which of the following does not require a TPM warning system reset/relearn procedure?

Accepted Answer

Tire pressure adjustment does not require a TPM (Tire Pressure Monitoring) system reset/relearn procedure. Adjusting the pressure in the tires does not alter the system's ability to monitor or recognize the pressure levels, unlike tire rotation, sensor replacement, or tire replacement, which can change the position or functionality of the sensors within the system.

Question 15

Tire sidewall markings are being discussed. Technician A says maximum load, traction, and wear ratings are indicated. Technician B says maximum inflation pressure, tread plies, and sidewall plies are indicated. Who is correct?

Accepted Answer

Tire sidewall markings include a variety of information such as maximum load, maximum inflation pressure, traction ratings, treadwear ratings, and the materials used in the tread and sidewall construction (tread plies and sidewall plies). Therefore, both Technician A and Technician B are correct in their statements.

Question 16

Technician A uses a head-type plug to repair a tire puncture in the tread area of a tire. Technician B injects tire sealant through the valve stem to repair a tire puncture in the sidewall. Who is correct?

Accepted Answer

Technician A is correct because using a head-type plug for a puncture in the tread area is an acceptable repair method. Technician B is incorrect because injecting sealant for a sidewall puncture is not a recommended repair method; sidewall damage typically requires tire replacement.

Question 17

Technician A says an incorrect wheel can affect tire clearance as well as speedometer and odometer calibrations. Technician B says the wrong size wheel can affect the antilock brake system. Who is correct?

Accepted Answer

Both technicians are correct. An incorrect wheel size can indeed affect tire clearance, speedometer, and odometer calibrations as mentioned by Technician A. Technician B is also correct because the wrong wheel size can impact the antilock brake system (ABS) operation, as the ABS relies on wheel speed sensors that can be affected by changes in wheel diameter.

Question 18

Technician A says tire tread patterns must be directional. Technician B says tire tread patterns must be symmetric. Who is correct?

Accepted Answer

Tire tread patterns can be directional, symmetric, asymmetric, or even unidirectional. There is no requirement for them to be exclusively directional or symmetric. Different tread patterns serve different purposes, such as wet grip, noise reduction, or wear characteristics.

Question 19

Technician A says rim diameter is determined by measuring across the rim between the flanges. Technician B says rim width is measured across the bead seating areas from the top to the bottom of the wheel. Who is correct?

Accepted Answer

The answer of Technician A says rim diameter is determined...

Question 20

Technician A says modern vehicles use tubeless tires. Technician B says only heavy-duty trucks use pneumatic tires. Who is correct?

Accepted Answer

Modern vehicles predominantly use tubeless tires for their efficiency and safety benefits. Pneumatic tires, which are air-filled, are used not only by heavy-duty trucks but by most vehicles, including passenger cars, making Technician B's statement incorrect.

Quiz 45: Tires and Wheels