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Fuel economy-maximizing behaviors - Wikipedia, the free encyclopedia
I did some hypermiling this winter in my car, I found I could do about 10-15% better traveling at lower speeds and working to minimize braking. Most of what I have read points to max efficiency around 40 MPH.
Efficient Speeds
Maintaining an efficient speed is an important factor in fuel efficiency.[citation needed] [1] Optimal efficiency can be expected while cruising with no stops, at minimal throttle[citation needed] and with the transmission in the highest gear[citation needed]. The optimum speed varies with the type of vehicle, although it is usually reported to be in the range of 35 to 55 mph[9][10] [11]. For instance a 2004 Chevrolet Impala had an optimum at 42 mph (70 kph), and was within 15% of that from 29 to 57 mph (45 to 95 kph)[9]. Drivers of vehicles with fuel-economy displays can check their own vehicles by cruising at different speeds and monitoring the readout.