I am a college student and I have a 01 f-250 diesel stock, other than a leveling kit and exhaust. The truck has been in my family and taken care of very well, I have to drive about 80mi a day on the highway and I am looking to up the mileage on it. I know a car seems smarter but I love the powerstroke and need a truck every now and then ( not for any heavy towing) I was thinking of changing out the gearing from the 4.10 to 3.55's, right now im getting about 17 around town and on the highway. What could I expect (mpg and rpm) from the switch? Also what kind of programmers and gear swap kits are going to be the most reliable? I am mechanically inclined and am going to do this myself.
2001 F-250 3.55 vs 4.10 gearing
- Thread starter dimes1989
- Start date
WD40
Full Access Member
Glad to have you here a SSD.com Always good to have another Texan here.
If you can get the gears for free and do all the work yourself it mite be worth it.
If you have to pay $500 to $900 bucks to change out the gears, then it would take for ever to get the pay back. A tuner mite be the best way for you to go. The right one should get you up around 20 to 22 MPG. with some training on how to use your right foot.
Doug
If you can get the gears for free and do all the work yourself it mite be worth it.
If you have to pay $500 to $900 bucks to change out the gears, then it would take for ever to get the pay back. A tuner mite be the best way for you to go. The right one should get you up around 20 to 22 MPG. with some training on how to use your right foot.
Doug
94f450sd
certified nutjob
with a higher gear you will lose MPGs around town especially if youre in an area with a ton of stop signs and redlights.but you will gain a little on the highway.
youd probably be better off with a programmer and a few other mods to open it up and let it breath.
youd probably be better off with a programmer and a few other mods to open it up and let it breath.
BJS
Full Access Member
bang for the buck slowing down will help the highway mileage the most. That being said the 10.5/10.25 is not a very difficult rear to setup gears on however if this is your primary or only vehicle I'd highly recommend paying someone to do it. If you have a 4wd truck keep in mind the front needs to be changed to match.
If you're truck is a 2wd truck, (or for experimental purposes) you may want to see what you can get a rear diff from the junk/salvage yards for, often these are cheaper than gears and setup on your axle if you're going to a ratio that was available from the factory; which were 3.71, 4.10, & 4.30 for the year you have.
the '97 & older trucks came with 3.55's that you're looking for but they are a different lug pattern & you loose the disc brakes in the rear.
If you're truck is a 2wd truck, (or for experimental purposes) you may want to see what you can get a rear diff from the junk/salvage yards for, often these are cheaper than gears and setup on your axle if you're going to a ratio that was available from the factory; which were 3.71, 4.10, & 4.30 for the year you have.
the '97 & older trucks came with 3.55's that you're looking for but they are a different lug pattern & you loose the disc brakes in the rear.