Thread: MPG Difference: 3.55 versus 3.73

Originally Posted by Ford Fan#1

since you said the truck would be used for interstate driving I would get the 3.55. Maybe even the 3.31. The 3.55 would be better for towing and have more "pickup" then the lower gearing. But the lower gearing will give you better fuel mileage and have less wear on your motor due to the Rpms being lower then what you would have if you had higher gears. But if you want big tires and go mod crazy then you want higher.

hears go opposite bud. 3.31 is a higher gear than 3.55 and 3.73 is lower.

Originally Posted by BFEB

hears go opposite bud. 3.31 is a higher gear than 3.55 and 3.73 is lower.

then why would it make the Rpms higher in overdrive at 60 if i have 3.73 and my dad has 3.55s? Not saying you are wrong just saying it doesn't make sense to me

Originally Posted by Ford Fan#1

then why would it make the Rpms higher in overdrive at 60 if i have 3.73 and my dad has 3.55s? Not saying you are wrong just saying it doesn't make sense to me

It's just how you say it.....4.10 gears are "lower" than 3.55

Originally Posted by Ford Fan#1

then why would it make the Rpms higher in overdrive at 60 if i have 3.73 and my dad has 3.55s? Not saying you are wrong just saying it doesn't make sense to me

it's because any gear # is a ratio to 1. So the closer the number is to 1 (direct drive) the higher the gear. That's also why it's called overdrive. Cause the gear ratio in your transmission for that gear is actually less than a 1:1 ratio ---------- The advertised gear ratio is simply the final drive ratio. Each gear in your tranny has its own ratio