Question 1

A vehicle equipped with a coil spring front suspension and a leaf spring rear suspension "dog tracks" while driving on a straight, level road. Technician A says that a broken center bolt could be the cause. Technician B says defective rear shock absorbers could be the cause. Which technician is correct?

Accepted Answer

Technician A is correct because a broken center bolt in a leaf spring can cause misalignment of the rear axle, leading to "dog tracking," where the vehicle doesn't travel straight even on a level road. Technician B's suggestion of defective rear shock absorbers wouldn't typically cause "dog tracking," as shock absorbers primarily affect the ride quality and control rather than the alignment of the vehicle's suspension or axles.

Question 2

When axle windup is controlled by the rear leaf spring during acceleration, the suspension type is called a ________.

Accepted Answer

The Hotchkiss drive uses the rear leaf springs to control axle windup during acceleration, making it distinct from other suspension types that might use additional components or mechanisms for this purpose.

Question 3

A loud "bang" is heard and felt every time the accelerator is depressed or released on a rear-wheel drive vehicle. Technician A says that a leaking shock absorber could be the cause. Technician B says that a broken torque arm could be the cause. Which technician is correct?

Accepted Answer

A broken torque arm can cause a loud "bang" when the accelerator is depressed or released, as it affects the stability and alignment of the drivetrain. A leaking shock absorber would not typically cause this symptom.

Question 4

Technician A says that leaf springs are mounted lengthwise on the rear of many vehicles. Technician B says that some vehicles use transversely mounted leaf springs on the rear. Which technician is correct?

Accepted Answer

Both technicians are correct. Leaf springs are commonly mounted lengthwise on the rear of many vehicles for suspension purposes. However, some vehicles also use transversely mounted leaf springs on the rear, although this is less common.

Question 5

A strut-type suspension is used ________.

Accepted Answer

Strut-type suspensions can be used in both the front and rear of vehicles, offering a compact and efficient means of combining the spring and shock absorber into a single unit.

Question 6

Two technicians are discussing rear shock absorbers. Technician A says that if one shock is leaking, then both rear shock absorbers should be replaced. Technician B says that the rear axle should be supported before removing the rear shock absorbers. Which technician is correct?

Accepted Answer

Both technicians are correct. Technician A is correct because if one shock absorber is leaking, it's recommended to replace both to ensure balanced handling and performance. Technician B is correct because supporting the rear axle is necessary for safety and to prevent damage when removing the rear shock absorbers.

Question 7

A "witness mark" is a ________.

Accepted Answer

A "witness mark" is a mark that indicates where two parts have rubbed or touched, often used to show alignment or contact points.

Question 8

The left front of the vehicle is higher than the right front and the right rear is lower than the left rear. What is the most likely cause of this problem?

Accepted Answer

A sagging right rear spring would cause the right rear of the vehicle to be lower than the left rear, and indirectly cause the left front to be higher than the right front due to the diagonal imbalance.

Question 9

One rear leaf spring is broken. Technician A says that both rear leaf springs should be replaced. Technician B Says that only the broken spring needs to be replaced. Which technician is correct?

Accepted Answer

Replacing both rear leaf springs ensures that they have the same strength and flexibility, maintaining vehicle balance and performance.

Question 10

A track rod is also called a ________.

Accepted Answer

A track rod is also called a Panhard rod, which is used in vehicles to maintain the lateral position of the axle.

Question 11

Technician A says that solid rear axles are used only in rear-wheel drive vehicles. Technician B says that solid rear axles are used in both front-wheel drive and rear-wheel drive vehicles. Which technician is correct?

Accepted Answer

Solid rear axles can be used in both front-wheel drive and rear-wheel drive vehicles, although they are more commonly associated with rear-wheel drive setups.

Question 12

Technician A says that a leaf spring suspension requires control arms to brace and position the rear axle. Technician B says that leaf springs help locate the axle under the vehicle. Which technician is correct?

Accepted Answer

Technician B is correct because leaf springs serve a dual purpose of both supporting the vehicle and helping to locate or position the axle under the vehicle, eliminating the need for separate control arms.

Question 13

Technician A says that trailing arms include any arm where the supported member trails the arm. Technician B says that trailing arms may also be called control arms on some vehicles. Which technician is correct?

Accepted Answer

Both technicians are correct. Trailing arms are a type of suspension component where the supported member (such as the axle or wheel hub) trails behind the pivot point of the arm, which is what Technician A describes. These components can also be referred to as control arms in some vehicle contexts, as mentioned by Technician B.

Question 14

Technician A says that a torque arm is designed to support the weight of the vehicle. Technician B says that a torque arm is designed to prevent rear axle wind up. Which technician is correct?

Accepted Answer

Technician B is correct because a torque arm is primarily designed to prevent rear axle wind-up by controlling the rotational forces between the axle and the vehicle's chassis, not to support the vehicle's weight.

Question 15

Technician A says that many unit body suspensions use struts on the rear. Technician B says that most full frame vehicles use struts on the rear. Which technician is correct?

Accepted Answer

Technician A is correct because many unit body (unibody) vehicles indeed use struts on the rear suspension due to their compact and efficient design, which is suitable for the integrated frame and body structure of these vehicles. Technician B is incorrect because most full-frame vehicles, which have a separate body and frame, typically use a different suspension setup, such as leaf springs or coil springs with separate shock absorbers, rather than struts.

Question 16

Technician A says that SLA suspensions reduce tire scrub. Technician B says that solid rear axles are used with independent rear suspensions. Which technician is correct?

Accepted Answer

Technician A is correct because Short Long Arm (SLA) suspensions are designed to minimize tire scrub during suspension movement, improving handling and tire life. Technician B is incorrect because solid rear axles are not used with independent rear suspensions; by definition, an independent rear suspension allows each wheel to move independently, whereas a solid rear axle links the wheels together.

Question 17

Technician A says that suspension diagnosis and service should begin with a comprehensive test drive.Technician B says that shocks or struts should be replaced in axle pairs. Which technician is correct?

Accepted Answer

Both technicians are correct. A comprehensive test drive is essential for diagnosing suspension issues effectively, as it helps identify symptoms and problems. Replacing shocks or struts in axle pairs ensures balanced handling and safety, preventing uneven wear and potential handling issues.

Question 18

Technician A says that all unit body vehicles have a track rod or stabilizer bar in the rear suspension. Technician B says that individual leaves of a leaf spring often crack before breaking. Which technician is correct?

Accepted Answer

Technician B is correct because individual leaves of a leaf spring can indeed crack before breaking, which is a common issue that can occur due to fatigue or overloading. Technician A is incorrect because not all unit body vehicles have a track rod or stabilizer bar in the rear suspension; this depends on the specific design of the vehicle's suspension system.

Question 19

Which of the following is a disadvantage of a solid rear axle?

Accepted Answer

A solid rear axle can lead to reduced tire adhesion due to less independent movement, increased unsprung weight which affects handling and comfort, and side to side shock transference where an impact on one side can affect the other side, all of which are disadvantages.

Question 20

Which of the following reduce tire adhesion (traction)?

Accepted Answer

All of these factors can negatively impact tire adhesion by affecting the stability and contact of the tire with the road surface.

Quiz 114: Rear Suspensions and Service