Ford bumps up the mileage on Super-Duty pickups
Ford has decided to make some mid-year running changes to bump the mileage on their biggest vehicles. The SuperDuty pickups generally have a hard time cracking the double digits but then they are designed as work trucks meant to haul large heavy loads. Nonetheless, anyone using one of these beasts to earn a living is bound to have concerns about the rising cost of fuel. Single rear wheel F-250 and F-350 models with the 6.4L diesel get lower final drive ratios going from 3.73:1 to 3.55:1. Combined with a 4-inch deeper chin spoiler helps to yield an extra 1.5mpg. Trucks with the 5.4L gas V-8 get a 0.5mpg bump thanks to a final drive ratio that goes from 4.10 to 3.73. In spite of the changes none of the trucks lose any towing performance. Regular cab diesel models still have a 12,500 lb tow rating.
[Source: PickupTruck.com]
Reader Comments (Page 1 of 1)
why not the LS2/LS7? 12:16PM (1/04/2008)
Note to editor:
In the crazy world of rear-ends, 3.73:1 is a "lower" rear end than 3.55:1. This is because it reduces the wheel speed more, just like 1st gear compared to 4th (i.e. like a "lower" gear).
3.55:1 can be called "numerically lower" (and usually is) or more simply "taller". Oddly, it is almost never called a "higher" rear end.
I'm fine with this change but it doesn't amount to much. This just amounts to changing the default final drive ratio, a full array of ratios was available before and are still available now. Many buyers will just order the lower rear end anyway.
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Phil L. 12:22PM (1/04/2008)
Huh?
>>In spite of the changes none of the trucks lose any towing performance.
The truck's tow *rating* might not change, but I'll bet towing *performance* will drop. Try telling this to someone near GCVWR at the bottom of a 10 mile grade - and they can't get the engine RPMs they need at the proper speed. Trucks pulling big loads are very sensitive to final drive ratio. This can be a big issue for those who use these trucks as they're intended.
As "who not..." alluded, there are also lots of folks out there who retrofit serious towing ratios (4.10 and "lower"), so I also question how effective this change will really be.
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why not the LS2/LS7? 2:35PM (1/04/2008)
Agreed Phil. Seems like the towing capacity was already limited by brakes or grip, not by torque. This change will decrease torque at low speeds, impacting uphill tows as you mention.
I disagree a bit that this is the only use for these trucks. Some just use them to carry heavy bed loads, which rarely reach the weight of towed items. So for those people, this change will be fine.
As always, those who tow will have to know and make sure they get the right setup before they buy or head out.
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