How should you drive through flood water?
- A Slowly, in a low gear, with engine speed high
- B Slowly, in a high gear, with engine speed low
- C As quickly as possible to cause the least delay
- D At normal speed when you have spray reducers fitted
Why this is the answer
It's important to use a low gear and keep the engine speed high to prevent water from entering the engine through the exhaust system. In these circumstances, it may be necessary to slip the clutch to keep the road speed as low as possible.
Why the other answers don't fit
- B
- Slowly, in a high gear, with engine speed low — A high gear with low revs risks stalling, and a stalled engine in water is hard to restart.
- C
- As quickly as possible to cause the least delay — Speed throws a bow wave and pushes water into the engine.
- D
- At normal speed when you have spray reducers fitted — Spray reducers deal with water from your wheels, not with driving through a flood.
Where this comes from
- Driving Buses and Coaches — section 9
- Driving Goods Vehicles — section 9
Rule numbers link to The Highway Code on gov.uk.
Where this question comes from
The question, its options and the explanation are reproduced word for word from the DVSA revision question bank under licence. The licence requires them to appear unaltered, so we cannot reword them and neither can anyone else — that is why you will meet the same wording on other sites. Everything else on this page is written by Theory Hub: the explanation of why each wrong answer is wrong, the topic guide and the revision notes.
Asked in: Lorry & Bus (LGV/PCV)
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