266. When you drive in the mountains, you will have to use lower gears to drive safely down grades. Which of these does NOT affect your choice of gears?
Detailed Explanation
The correct answer is "Tire tread type.". This question tests general CDL knowledge and the safest action expected of a commercial driver. Because the prompt uses negative wording, identify the normally correct safety rules first, then select the exception.
Correct Answer: Tire tread type.
Why This Matters on the CDL Test
Use this as part of your General Knowledge review. The real CDL knowledge test rewards drivers who understand the reason behind each rule, not only the answer letter, so read the explanation and then try a few related questions.
How to Remember It
Say the rule in your own words, then explain why the wrong answers are unsafe or incomplete. That habit makes similar General Knowledge questions easier when the exam changes the wording.
Answer Review
Choose "Tire tread type." because this answer matches the safe CDL action for transmission types and gear selection. On the knowledge test, the safest answer is usually the one that protects space, control, visibility, legal compliance, or inspection accuracy before the vehicle is put at risk.
Why the other answers are weaker
- Weight of the load."Weight of the load." does not best answer this transmission types and gear selection question. When you see a similar option on the CDL permit test, compare it against the exact safety rule and choose the answer that prevents the most immediate risk.
- Length of the grade."Length of the grade." does not best answer this transmission types and gear selection question. When you see a similar option on the CDL permit test, compare it against the exact safety rule and choose the answer that prevents the most immediate risk.
Test-Day Checklist
- Read the question once for the topic, then read it again for the exact CDL action being tested in General Knowledge.
- Eliminate answers that sound convenient but skip an inspection, warning sign, or safety step.
- Say the correct rule out loud before moving on so you can recognize it when the exam changes the wording.
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Start Practice TestRelated Questions
307. When driving on grades, which of these is the best choice for a safe speed?
124. Tank vehicles are used to carry any liquid and are dangerous to drive because:
140. You must drive on a slippery road. Which of these is a good thing to do in such a situation?
185. You can safely remove the radiator cap as long as the engine isn't overheated.
196. You are driving a vehicle that could safely be driven at 55 mph on an open road; but traffic is now heavy, moving at 35 mph, although the speed limit is 55. The safest speed for your vehicle in this situation is most likely:
Keep Studying General Knowledge
Question pages help you review one rule at a time. To build test-day speed, move back into the full General Knowledge practice test and answer a mixed set without looking at the explanation first.
State CDL Practice Paths
After you understand this answer, use a state practice path to connect the federal CDL rule with the DMV test pages drivers search for most.