Which condition is associated with the use of retarders on a vehicle with poor drive-wheel traction?

Which condition is associated with the use of retarders on a vehicle with poor drive-wheel traction?

• A. Skidding
• B. No effect
• C. Improved braking
• D. Faster stop

Answer: (A)

The key idea is that braking force must stay within what the tire-road grip can support. A retarder adds braking torque to the drive wheels without using the service brakes, so on a surface with poor traction that extra force can exceed the available grip. When that happens, the wheels stop rotating and begin to slide across the road, producing a skid. So, on a vehicle with poor drive-wheel traction, using retarders is associated with skidding.

The key idea is that braking force must stay within what the tire-road grip can support. A retarder adds braking torque to the drive wheels without using the service brakes, so on a surface with poor traction that extra force can exceed the available grip. When that happens, the wheels stop rotating and begin to slide across the road, producing a skid. So, on a vehicle with poor drive-wheel traction, using retarders is associated with skidding.