How much would my gas mileage increase if i put in a higher gear ratio in my truck?
Written by The Wiz on May 1st, 2008
Countryboy asked: I have a 3 speed auto transmission and when it goes out i might put a 4 speed auto transmission would that increase gas mileage by a good bit. I drive a 1978 GMC Jimmy that gets 10 miles a gallon.