Difference in Gearing
Hello! I recently sold my truck to move to a crew cab. I have come across two F-150's that are very similar save the rear end gear ratio. One has the 3.55 and the other the 3.73. The difference in ...
Forum Discussion
Forget about saving gas with the 3.55 gears. These are great to improve freeway EPA MPG figures by 1 MPG and have no impact on around town or towing MPG. On the other hand the taller gears will make for slower acceleration at freeway on ramps or when passing slow moving big rigs on steep grades.
The taller gears offered no advantage in terms of fuel economy with 4-speed transmissions and with current 6-speed and 8-speed transmissions there is really no reason to go with the higher gearing for any vehicle much less one that will be used to tow. With my truck's 6-speed transmission there are TWO overdrive gears. With the 4-speed transmission I had none.
Ford is the worst in this regard with too high gearing and they have to do this when they sell so many trucks which pulls down their fleet mpg for meeting the federal CAFE requirements. Makes sense for Ford to respond by using gears that are too tall but it does nothing for their customers.
The taller gears offered no advantage in terms of fuel economy with 4-speed transmissions and with current 6-speed and 8-speed transmissions there is really no reason to go with the higher gearing for any vehicle much less one that will be used to tow. With my truck's 6-speed transmission there are TWO overdrive gears. With the 4-speed transmission I had none.
Ford is the worst in this regard with too high gearing and they have to do this when they sell so many trucks which pulls down their fleet mpg for meeting the federal CAFE requirements. Makes sense for Ford to respond by using gears that are too tall but it does nothing for their customers.
