Under normal driving conditions, it's best to shift in the 2,000 to 3,000 rpm. range. You will get the best gas mileage & the least amount of engine wear. R.P.M. means revolutions per minute. During daily driving, only foolish people or people that plan to sell their cars early rev/shift at high RPM. That is why I would not buy a car from a young guy with an awesome sounding exhaust
