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Hi, this is not a question specific to the vehicle mentioned but it is more general, does the fuel consumption vary with revs? for example, if I was higher in the rev range in 2nd gear at 30mph but low in the rev range at 100mph would that mean I consume more fuel at 30 due to the higher revs or at 100?. Exclude the acceleration up to those speeds just use it as an average.

Answers from the Automotive Experts

Jessica Howe, Automotive Expert & Coach at


Thank you for writing in. Typically, the higher of a gear you are in the more fuel efficient the engine is running. However, this is only true if the speeds are consistent and lower than 70 MPH. Higher speeds will still cause the engine to use more fuel. While it is impossible for me to say whether you would be more fuel efficient at 30 MPH at high RPMs or at 100 MPH in lower RPMs, it is likely that you are not as fuel efficient as you could be in either situation. You will be most fuel efficient going 65 MPH in a higher gear. This is why we measure gas mileage both in city (with lots of stops and gos) and on the highway (in a higher gear at constant speeds). 

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