DFFT Tires and Wheels 3

Question 1

A driver reports that the steering wheel shimmies (oscillates side to side) at around 45–55 mph but is smooth at other speeds. What is the most likely cause?

Accepted Answer

Static or dynamic wheel imbalance

Answer

Bent steering tie rod

Answer

Worn front strut bearings

Answer

Incorrect tire pressure

Question 2

After replacing a front tire, a technician performs a wheel alignment check. Which alignment angle, if incorrect, would most directly cause rapid tire wear on the inner edge only?

Accepted Answer

Camber

Answer

Caster

Answer

Toe

Answer

Thrust angle

Question 3

A vehicle's tires are properly inflated and the tread depth is adequate, but the driver reports poor wet-weather traction. What tire-related fault should be inspected first?

Accepted Answer

Hardened or glazed tread compound from age or heat cycling

Answer

Incorrect wheel offset

Answer

Loose lug nuts

Answer

Rim corrosion

Question 4

What would happen if a vehicle is driven with mismatched tires — one radial and one bias-ply — on the same axle?

Accepted Answer

Unpredictable handling and uneven cornering forces due to different flex characteristics

Answer

Reduced braking distance on dry roads

Answer

Improved fuel economy from lower rolling resistance

Answer

No noticeable difference in normal driving conditions

Question 5

During a wheel inspection, a technician notices that several lug nuts on a wheel are loose. What is the most serious risk if the vehicle is driven in this condition?

Accepted Answer

The wheel can detach from the vehicle while in motion

Answer

The wheel studs will corrode prematurely

Answer

Tire bead separation from the rim

Answer

Wheel bearing overheating

Question 6

A driver notices the vehicle drifts to the right on a level road, but the tires appear to be at equal pressure. After ruling out brake drag, what tire condition should be checked next?

Accepted Answer

Tire conicity — a manufacturing defect causing the tire to act like a cone

Answer

Tread depth difference between left and right front tires

Answer

Overloading of the right rear tire

Answer

Valve stem position on the right front tire

Question 7

What is the correct procedure when installing a tire on a split-rim (multi-piece) wheel to prevent a dangerous blowout during inflation?

Accepted Answer

Place the assembled wheel in a safety cage or restraining device before inflating

Answer

Inflate the tire slowly while holding the rim lock in place by hand

Answer

Inflate the tire to seating pressure before installing the lock ring

Answer

Lay the wheel flat on the ground and stand behind it while inflating