Which of these is true about retarders and fuel economy?

They have no effect.. Retarders slow the vehicle without using brakes, but they don't directly save fuel in terms of MPG, though they save

Which of these is true about retarders and fuel economy?

ANSWER BREAKDOWN
  • A. Incorrect. "They use more fuel." is not correct. Retarders slow the vehicle without using brakes, but they don't directly save fuel in terms of MPG, though they save brake wear.
  • B. Incorrect. "They save fuel by reducing the need to accelerate." is not correct. Retarders slow the vehicle without using brakes, but they don't directly save fuel in terms of MPG, though they save brake wear.
  • C. Correct. Retarders slow the vehicle without using brakes, but they don't directly save fuel in terms of MPG, though they save brake wear.
  • D. Incorrect. "They only work when the engine is off." is not correct. Retarders slow the vehicle without using brakes, but they don't directly save fuel in terms of MPG, though they save brake wear.