Dually gearing - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars
Ford F-100 | Ford F-150 | Ford F-250 | Ford F-350 | Ford Super Duty | Ford Diesel Forum for discussion of the Ford F100, F150, F250, F350, Superduty and Diesel trucks.

LinkBack Thread Tools Display Modes
post #1 of 3 (permalink) Old 09-05-12, 08:03 AM Thread Starter
Registered User
Join Date: Sep 2012
Location: Iowa
Posts: 1
Dually gearing

I have a 06 F350 dually. Not 100 percent sure but I think it has 410 gears in it, when I am goin 60MPH my tach is running 2000. My buddies F350 SRW runs 2 grand at 73mph. So I am thinking of changing gears and would like any input on this subject. Like cost and effects. The only thing I pull is a 9000 lbs camper with my Harley in the back of my truck. I am thinking this will have a pretty good affect on my MPG?

Ironwork111 is offline  
Sponsored Links
post #2 of 3 (permalink) Old 09-05-12, 09:37 AM
2002 F150 XLT
Bert's Avatar
Join Date: Nov 2008
Location: Oregon
Posts: 10,453
Re: Dually gearing

That would help the mileage. The power would drop though. If you figure the miles you drive per year and the difference in mileage, how much more would the gas cost? Check this to see how much you'd save per year. DollarTimes.com | Gas Savings Calculator

Bert is offline  
post #3 of 3 (permalink) Old 09-16-12, 12:36 PM
360ci's Avatar
Join Date: Nov 2007
Location: Waterloo
Posts: 2,481
Re: Dually gearing

SRW and DRW run different tire sizes (overall diameter is slightly taller with the SRW) so by going to a lower gear set (if you have 4wd, you'll need to change both axles) won't net you that much change in RPM at any given speed. The different between 4.10 and 3.73 (knowingly what your friend has) isn't really worth the $750 or so it will cost to change the gear sets from what you'll save in fuel. If you drive 15K miles a year it'll take you a good 5-7 years to pay for that.

The downside, 4.10 is what you want when towing several tons of anything. Taller gears allow you to drive in a higher gear without lugging the engine which can thus cause erratic shifting (excessive heat can cause transmission failure). If you can tow in top gear (overdrive) now, you may find yourself pulling the trailer in a lower gear not only to prevent gear hunting, but you will have minimal throttle response when you have to climb even a 4% grade, and will need to downshift or lose speed. In this case, mileage will be worse.

If you don't tow often and drive the truck empty on a somewhat normal basis, 3.73 gears will save a bit of mileage if you prefer to drive over 65mph on a regular basis. If you drive mostly in town empty, the 4.10s will be the ones to have as lower gears will get you up to a set speed quicker and thus save mileage.

'11 Ram Quad Cab 4x4 SXT 5.7L HEMI (stock); 48,500m
'06 Pontiac G6 GT 3.5L 220hp; 64,000m
'12 Chrysler 200 Limited 3.6L 283hp; 28,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
Amsoil in all vehicles!
360ci is offline  
Sponsored Links

  Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars > Ford Trucks | Utes | Vans |SUVs | Crossovers > Ford F-100 | Ford F-150 | Ford F-250 | Ford F-350 | Ford Super Duty | Ford Diesel

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome