01 F350 4.10 or 3.73 i have 38in toyos
#16
01-15-2013, 10:35 PM
#17
01-15-2013, 11:56 PM
Cargo Master
I would say either 4.30 gears or 4.56 gears. That would be my suggestion for someone that dosent ever plan to pull anything heavy. The 4.30 is a stock gear ratio and could likely be sourced used in stock axles. As for mpg. You could always walk that would be 100% increase in fuel economy. But seriously anything better that 10mph in a truck that size with that much going against fuel economy would be reasonable.
#18
01-16-2013, 08:21 AM
you may see some benefit to lower gears due to the extra rotating weight of the tire combo. if your 38's weighed the same as your stock tires (they dont!) then a gear ratio close to stock would result in fuel mileage close to stock.
think how much harder the wheels are to get moving .... that tire combo weighs a TON compared to the stock combo and as such your mileage will always be lower with the big skins.
as others have said, 4.56 gets you back to the stock gearing.
you may benefit from adding a little gear, making those big tires a little easier to get rolling, thus keeping your foot out of the throttle a little on the take off and up hills.
if this were a gas motor i'd say put some 5.13's in it and be done. 5.13's would be roughly equal to 4.30's stock.
being a diesel, you may not want to go that deep. i think your best bet is somewhere between 4.56 and 5.13...... so, if it were my truck trying to achieve what you are trying to achieve .... i'd go with 4.88's and consider it a good compromise.
do what you think is right!
think how much harder the wheels are to get moving .... that tire combo weighs a TON compared to the stock combo and as such your mileage will always be lower with the big skins.
as others have said, 4.56 gets you back to the stock gearing.
you may benefit from adding a little gear, making those big tires a little easier to get rolling, thus keeping your foot out of the throttle a little on the take off and up hills.
if this were a gas motor i'd say put some 5.13's in it and be done. 5.13's would be roughly equal to 4.30's stock.
being a diesel, you may not want to go that deep. i think your best bet is somewhere between 4.56 and 5.13...... so, if it were my truck trying to achieve what you are trying to achieve .... i'd go with 4.88's and consider it a good compromise.
do what you think is right!
#19
01-16-2013, 05:34 PM
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