DFFT Steering and Suspension 2 — Questions and Answers
Question 1: A vehicle's power steering becomes heavy and difficult to turn at low speeds. What should be checked?
- Power steering fluid level and the drive belt condition (Correct answer)
- Front wheel alignment toe setting
- Tire inflation pressure on both front tires
- The steering column universal joint for binding
Correct answer: Power steering fluid level and the drive belt condition
Low power steering fluid or a slipping drive belt reduces the hydraulic pump's ability to generate sufficient pressure to assist steering at low speeds.
Question 2: A vehicle produces a whining noise that varies with engine speed when turning the steering wheel. What is the cause?
- A low power steering fluid level causing the pump to cavitate (Correct answer)
- A worn steering rack causing internal leakage
- A dry or worn steering column upper bearing
- A faulty electric power steering motor
Correct answer: A low power steering fluid level causing the pump to cavitate
When the power steering reservoir is low, the pump draws air along with fluid, causing cavitation that produces a whining or groaning noise that changes with pump speed.
Question 3: Cupped or scalloped wear appears on all four tires. What suspension component is the most likely cause?
- Worn or failed shock absorbers allowing excessive wheel bounce (Correct answer)
- Incorrect toe alignment on all four wheels
- Wheel bearing looseness allowing wheel wobble
- Unbalanced tires on all four corners
Correct answer: Worn or failed shock absorbers allowing excessive wheel bounce
Worn shock absorbers allow uncontrolled wheel hop, causing the tires to periodically bounce away from the road surface and create uneven scalloped wear patterns.
Question 4: A vehicle dips severely at the front during braking and squats at the rear during acceleration. What is the most likely cause?
- Worn front and rear shock absorbers or struts (Correct answer)
- Incorrect spring rate for the vehicle's weight
- Air in the power steering hydraulic system
- A broken rear anti-roll bar
Correct answer: Worn front and rear shock absorbers or struts
Shock absorbers dampen spring movement; worn dampers allow excessive body motion, leading to nose dive under braking and squat under acceleration.
Question 5: During a vehicle inspection you find a torn outer CV joint boot with grease flung around the area. What must be done?
- Replace the CV joint boot and inspect the joint for damage and repack with grease (Correct answer)
- Clean the grease off and monitor the joint at the next service
- Replace the entire driveshaft as the CV joint is certainly destroyed
- Pack the joint with grease through the tear and seal it with tape
Correct answer: Replace the CV joint boot and inspect the joint for damage and repack with grease
A torn CV boot allows contamination to enter the joint and grease to escape; the joint must be inspected for damage and repacked before a new boot is installed.
Question 6: A clicking noise from the front of the vehicle only occurs during turns at low speed. What component is most likely faulty?
- An inner or outer CV joint on the front driveshaft (Correct answer)
- A worn front wheel hub bearing
- A loose front brake caliper bolt
- A worn front lower ball joint
Correct answer: An inner or outer CV joint on the front driveshaft
CV joints produce a characteristic clicking noise during low-speed turns when they are worn, as the balls are loaded unevenly at extreme joint angles.
DFFT Steering and Suspension 2
A vehicle's power steering becomes heavy and difficult to turn at low speeds.
What should be checked?