When adjusting your mirrors, what should you see in the inside vertical edge of your plane mirrors?

When adjusting your mirrors, what should you see in the inside vertical edge of your plane mirrors?

• A. Part of the trailer.
• B. A point on the ground 35 feet away.
• C. The trailer body.
• D. A point on the ground 30 feet away.

Answer: (C)

When you’re adjusting the mirrors on a tractor-trailer, the inside vertical edge of each plane mirror should show the trailer body. This placement gives you a reliable view of the trailer directly behind and aligned with your cab, so you can monitor its position, detect drift, and maintain proper clearance. Seeing a ground point in that edge would indicate the mirror isn’t angled correctly for monitoring the trailer, and you wouldn’t get the useful view of the trailer body you need.

When you’re adjusting the mirrors on a tractor-trailer, the inside vertical edge of each plane mirror should show the trailer body. This placement gives you a reliable view of the trailer directly behind and aligned with your cab, so you can monitor its position, detect drift, and maintain proper clearance. Seeing a ground point in that edge would indicate the mirror isn’t angled correctly for monitoring the trailer, and you wouldn’t get the useful view of the trailer body you need.