New Driver & CDL Skills · Driver Training VideoMirror Setup & Blind Spots

Start with this fact: your truck has four blind spots, and they're bigger than most drivers think. Directly in front of your hood, you're blind for about 20 feet — long enough to swallow a car that cuts in too close after a pass.

That means mirror setup isn't a formality. It's not something you glance at once and forget. Two exterior mirrors — one on each side — are required by federal rule, full stop. Most rigs add a convex spot mirror to widen that view.

Set your mirrors before you move, not after. You should be able to see a sliver of your own trailer in each flat mirror, plus a clear strip of the lane beside you. If you can see too much trailer and not enough lane, you've built yourself a bigger blind spot, not a smaller one.

Backing up is where mirror habits either save you or cost you. Both mirrors, both sides, every time — and if you lose sight of what's behind you for even a second, stop and get out to look, or get a spotter. A dent in a loading dock is a bad day.

Your company standard: check your mirrors during every pre-trip, re-adjust after any load change or driver swap, and never — never — trust one quick glance before a lane change: check, lean forward to look around the mirror, and check again.