Following a commercial vehicle — Minnesota Permit Test

Following a commercial vehicle on the Minnesota permit test — 6 rules, each with the reason behind it and a question on it while it is fresh.

The rules

An average car at 55 mph stops within 130 to 140 feet, while a fully loaded tractor-trailer may need more than 400 feet.

Three times the distance means the truck behind you cannot stop for what you stopped for.

A fully loaded tractor-trailer may need more than 400 feet to stop completely.

Minnesota Driver’s Manual, p.51

Following a commercial vehicle too closely cuts down what you can see of the road ahead.

The trailer is a wall. Behind it you are driving on the truck driver’s reactions instead of your own.

Following a commercial vehicle too closely reduces your ability to see the road ahead.

Minnesota Driver’s Manual, p.51

Position your vehicle so the truck driver can see you in their side mirrors.

If you cannot see the mirrors, the driver cannot see you, and they will change lanes anyway.

Maintain a safe following distance and position your vehicle so the driver can see you in their side mirrors.

Minnesota Driver’s Manual, p.51

When following a commercial vehicle at night, always dim your headlights.

A truck’s big mirrors throw your high beams straight into the driver’s eyes.

Commercial vehicles have large side mirrors that can reflect light. When following a commercial vehicle at night, always dim your headlights to avoid blinding the driver.

Minnesota Driver’s Manual, p.51

A merging commercial vehicle needs more time than a car to reach normal speed, so be ready to slow down or change lanes.

A loaded truck takes half a mile to reach highway speed, and it is merging into your lane.

When a commercial vehicle merges into traffic, it needs more time than a car to accelerate and reach normal speed.

Minnesota Driver’s Manual, p.51

Stopping behind a commercial vehicle on an upgrade, leave space for it to roll back slightly as it starts.

A heavy truck rolls back a foot or two before the drive takes hold, and your bumper is there.

If you stop behind a commercial vehicle on an upgrade, allow space for the truck to roll back slightly when it starts to move.

Minnesota Driver’s Manual, p.51

On the test

How far may a fully loaded tractor-trailer need to stop from 55 mph?

More than 400 feet. Three times the distance means the truck behind you cannot stop for what you stopped for. Minnesota Driver’s Manual, p.51: “A fully loaded tractor-trailer may need more than 400 feet to stop completely.”

How this works

Most practice tests hand you a bank of questions and leave the manual somewhere else. This one puts them together.

You read one law and the reason behind it, then answer a question on that law while it is still fresh. Get it right and you move on; get it wrong and you have found the gap while it is cheap to fix, not on the morning of the exam.

Learning one rule at a time, and proving it immediately, is what turns a manual you skimmed into something you actually know — and it makes studying feel like getting somewhere rather than like waiting to find out.

What it costs

  • One payment, once — not a subscription. Nothing renews and there is nothing to cancel, for an exam you sit one time.
  • Free to start: a 10-question test and the first section of cards. No sign-up and no account.
  • Paying opens the rest of the cards, unlimited full-length practice tests, and retests built from exactly the questions you got wrong.
  • Every level up to Prepared — 3 tests passed in a row.
  • Do the work, fail the real exam, and we refund you.

All Minnesota permit topics

Where these come from

Every rule here is checked against Minnesota Driver’s Manual, published by the Minnesota Department of Public Safety, and against the state code itself. Last checked 2026-09-22.