Practice question

For the Washington CDL Air Brakes knowledge test, when should engine retarders (Jake brakes) be used with caution or turned off?

  1. When fully loaded
  2. On wet, icy, or slippery roads, where they can cause the drive wheels to lose traction and skid
  3. When climbing
  4. In daytime

Answer: B — On wet, icy, or slippery roads, where they can cause the drive wheels to lose traction and skid

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