EBinMT

so flipping through my manual, I stumbled across some claims I hadn't heard before.

pg 413 "driving at resonable speeds(traveling at 55mph uses 15% less fuel than travelling at 65mph)."

pg 414 "Carrying unnecessary weight may reduce fuel economy (aproximately 1mpg is lost for every 400lbs of weight carried)."

Had any of you heard these claims before, and better yet are they verified? I believe the first, but the second may be a stretch.

eztarget

I can see it. I took a trip with a truckload of passengers and I surely didn't get what I was expecting on gas mileage. I did have a strong head wind going. If you think about it though, seems plenty state 10-12MPG on highway towing. Normally you should get somewhere around 20 right? What is the average towing weight? My guess is it is close to working out right. Of course I may be completely wrong too.

kozal01

iTrader: (2)

Whats not to believe its simple physics. Moving more weight means more power is used to maintain a speed meaning a decrease in mileage. Same with traveling slower, the truck works harder to maintain 65 MPH than it does to maintain 55 so mileage of coarse will be better at 55. That info is nothing new and its good to see the manufacturers adding that to the manual so people cant complain to them when they dont get 20 MPG while going 85 while pulling a trailer.

EBinMT

1mpg for every 400. what is the weight difference between a RCSB and Screw 6.5". 1000lbs or so? If so my truck should get 2.5MPg less than sticker?

EBinMT

I understand the loses are inevitable, but I had never seen actual values like the ones given. I can believe the 15%, but think the 1mpg per 400lbs is likely an over generalization, and must be for payload only as a 11,000lb tow would equate to losing 28mpg.

pat247

iTrader: (1)

The rule of thumb for weight reduction was 100 lbs = .1 mpg at the company I worked for.

ji603

I would agree that higher speeds = more wind resistance, so a bigger hit to mileage is expected traveling faster on the freeway where speed/profile/wind resistance is more relevant.

During city driving, profile makes less of a difference, and speeds aren't as high, so wind resistance is less of a factor too. Instead, more weight/mass, coupled with frequent stop and go, kills mileage.

I believe their numbers.

bajaman

Cool. I'd never seen an owner's manual post actual numbers before. Typically it just has the generic "for best mileage do blah blah blah blah blah....".

Like anyone cares about mileage if they bought a truck....lol!