You are driving a heavy vehicle with a manual transmission. You have to stop the vehicle on the shoulder while driving on an uphill grade. Which of these is a good rule to follow when putting it back in motion up the grade?
- A Keep the clutch slipping while slowly accelerating
- B Use the parking brake to hold the vehicle until the clutch engages
- C Let the vehicle roll straight backwards a few feet before you engage the clutch
- D Let the vehicle roll backwards a few feet before you engage the clutch, but turn the wheel so that the back moves away from the roadway
Correct answer: B — Use the parking brake to hold the vehicle until the clutch engages
CDL drivers are held to a stricter standard: a BAC of 0.04% or higher disqualifies you from driving a commercial vehicle. A first conviction for driving under the influence results in at least a one-year disqualification, and a second conviction results in a lifetime disqualification.
Why this matters
This question comes from the General Knowledge portion of the CDL knowledge exam, which is built directly from the AAMVA Commercial Driver License Manual. The rule it tests is one that examiners return to repeatedly — different exam forms may rephrase the question or change the example, but the underlying answer stays the same. Understanding the rule (rather than memorizing the wording) is what gets you past every variant.
Commercial driving is governed by the Federal Motor Carrier Safety Regulations (49 CFR Parts 350–399). State licensing agencies adopt these rules and add their own road and weight regulations on top. When you study for the CDL exam you are not just studying for a quiz — you are learning the rules you will be expected to follow on every trip, in every state, for as long as you hold the license. A driver who can answer this question correctly is one step closer to safe, professional operation.
Tips for studying this material
- Read the corresponding chapter of your state's CDL handbook in addition to practicing here.
- If you miss a question, write the rule down in your own words and revisit it 24 hours later.
- Connect each rule to a real driving scenario — visualizing the situation makes the answer easier to remember on test day.
- Practice in short sessions (15–25 minutes) rather than long marathons. Spaced repetition is more effective for long-term recall.