When choosing a safe speed for a long mountain downgrade, which factors must be considered?
Correct answer: D – All of the above
Montana’s CDL guidance lists vehicle and cargo weight, grade length, grade steepness, road conditions, and weather as factors in selecting a safe downhill speed. A heavier vehicle or steeper, longer grade places greater demands on the braking system. Slippery or poor road conditions require additional speed reduction.
Source: Montana Commercial Driver License Manual 2026 — § 2.16.1, “Select a ‘Safe’ Speed”


