Ford Fuel Economy

[More Power]

As reported in 8-Lug magazine, Ford, in an effort to address consumer complaints about low fuel economy with its new 6.4L PSD, will be replacing the 3.73 differential gear ratio with 3.55, and will add a new front air dam that extends another 4" below the front bumper to help with aerodynamics. Ford is expecting an increase of 1.5-mpg in its single-rear-wheel Superduty trucks. Towing performance and GCVWR are supposed to be unaffected.

Gearing and wind resistance are important factors in fuel economy...

Jim

[OC_DMAX]

They need to down size the truck and lighten it up a bit. Those things are huge! The front end is like pushing a house wall in front of you.

I do not know much about the Ford transmission, but I assume that it is not a 6-speed (correct?). GM effectively got a lower numerical rear-end when they brought out the 6 speed Allison.

[More Power]

Ford's Torque-Shift is a 5-speed (trans specs are here (http://www.thedieselpage.com/duramax/2007PullOff.htm)). Ford has sold a lot of Super Duty trucks because a good share of the truck buyers like the big-n-tall look. It is impressive looking, but you're right, it would have to affect fuel economy.

Jim

[ronniejoe]

Personally, I didn't think that they could make those Super Dutys look any worse... Boy! Was I wrong! Those newest Super Dutys are the ugliest trucks I've ever seen.:eek:

[DieselMonk]

They need to down size the truck and lighten it up a bit. Those things are huge! The front end is like pushing a house wall in front of you.

I do not know much about the Ford transmission, but I assume that it is not a 6-speed (correct?). GM effectively got a lower numerical rear-end when they brought out the 6 speed Allison.

No, still 3.73 on da 6 Speed Ally... nuttn changed.

[DmaxMaverick]

No, still 3.73 on da 6 Speed Ally... nuttn changed.

I think that's what he meant. Final drive ratio may have been a better choice of terminology.

[OC_DMAX]

No, still 3.73 on da 6 Speed Ally... nuttn changed.

Your correct in that the actual rear-end ratio did not change (from 5-speed to 6-speed Allison models), same axle and differential ratio (3.73) as it has always been since 2001.

However, GM "effectively" achieved a 3.20 differential ratio (someone can check my math!) by just adding a 6th speed (2nd overdrive) to the Allison (relative to the 5-speed Allison). Ford could have achieved the same "if" they had a 6-speed tranny.

[Runaway_Dmax]

I thought when the new 6.4 came out that it was mated up with a 6 spd auto also. Guess I will have to wander over there again to see. I'm sure when I was comparision shopping it had the 6-speed auto.:confused:

[gophergunner]

Why does it seem that all the new trucks are getting bigger, while still only doing what an older and much smaller truck would do, and people complain about the fuel mileage with the newer and bigger trucks...?

I'm not sure about everyone else........but I think the truck styling is getting farther away from my personal preference. I keep telling everyone I may just have to drive mine until it dies on me, as I rather enjoy the looks of it and it seems to get pretty good mileage.

[Runaway_Dmax]

I thought when the new 6.4 came out that it was mated up with a 6 spd auto also. Guess I will have to wander over there again to see. I'm sure when I was comparision shopping it had the 6-speed auto.:confused:

My mistake - only a 5 speed!

[Dakster]

Instead of researching what to do to get an extra 1.5 mpg at the most out of them, they need to research why so many motors grenade themselves before they hit 1,000 miles on the motor.

I know many people that bought the new Fords and within a month blew the motors. These weren't modified either. One was a tow truck company that bought two 2008 PSD's and within the same week both were in the shop with blown motors... I don't wish this on anyone. Ford, GM, or Dodge... I want them all to be reliable trucks. America needs each of them to survive.

[Nice Road Trucker]

I get pretty decent MPG out of a 2000 F-350. 27.5 summer, 24 winter on a circuit that is 35% urban/suburban, 35% rural two-lanes, and 30% Interstate.

Unlike the Cummins MPG poseurs I run the posted limit and along with the traffic in-town.

I have modded the truck for MPG. 3.08 gears, aero mods, and adjustment of the nut behind the wheel.

The poor 6.4 has no chance of getting decent MPG with all that Tier II junk hung on it.

BTW, I tow everything you can hang on the OEM hitch just fine. IMO, most trucks are wildly overgeared.