Clean all windows and glass — Montana Permit Test
Clean all windows and glass on the Montana permit test — 6 rules, each with the reason behind it and a question on it while it is fresh.
The rules
Keep the windshield clean, since bright sun or headlights on a dirty windshield make it hard to see.
Driving into a low sun, a smeared windshield turns into a white sheet of glare.
Keep the windshield clean. Bright sun or headlights on a dirty windshield make it hard to see.
Use antifreeze wash in your washer bottle where the temperature could fall below freezing.
Plain water freezes on the glass the moment you spray it in winter.
Use antifreeze wash in areas where the temperature could fall below freezing.
Smoking in the vehicle causes a film to build up on the inside of the glass.
That film lights up in oncoming headlights and hides the road at night.
Smoking causes a film to build up on the inside glass.
Clear snow, ice or frost from all windows, front, sides and back, before you drive.
Peeking through a small hole in the frost hides the car coming from the side.
Clear snow, ice, or frost from all windows. Clean the front, sides, and back before you drive.
Do not hang things from your mirror or clutter up the windshield with decals; they could block your view.
A swinging air freshener can hide a walker stepping into the crosswalk.
Do not hang things from your mirror or clutter up the windshield with decals. They could block your view.
Keep headlights, backup, brake and taillights clean; dirt on the lenses can cut their effectiveness by 50%.
A coat of road grime makes your brake lights look dim to the driver behind.
Keep the headlights, backup, brake and taillights clean. Dirt on the lenses can cut the lights' effectiveness by 50%.
On the test
Why does the manual say to keep your windshield clean?
Glare on dirt makes it hard to see. Driving into a low sun, a smeared windshield turns into a white sheet of glare. Montana Driver Manual, p.18: “Keep the windshield clean. Bright sun or headlights on a dirty windshield make it hard to see.”
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.
Where these come from
Every rule here is checked against Montana Driver Manual, published by the Montana Department of Justice, and against the state code itself. Last checked 2026-10-04.
- src/assets/drivers-manuals/MT.pdf (Montana Driver Manual, Revised April 2024, Montana Department of Justice, Motor Vehicle Division, retrieved 2026-09-14 and re-checked 2026-10-04; sha256 pinned in SOURCES.json)
- src/assets/drivers-manuals/MT.pages.txt (scripts/mt-text.sh: pdftotext -layout except printed pp.24-26, which are plain; the fixture every citation here was cut from and verified against; sha256 pinned in SOURCES.json)
- src/assets/drivers-manuals/MT-exam.html (Administrative Rules of Montana 23.3.121, Road Signs and Road Rules, as reproduced by the Legal Information Institute, read 2026-10-04; states the seven-miss pass mark; sha256 pinned under examSource)
- https://mvdmt.gov/forms-driver-license/ (read 2026-10-04; links the manual)