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cdlaine's avatar
cdlaine
Explorer
May 25, 2013

Found on Cummins diesel site.....

Team...

Just starting to build my own "+/-" database/spreadsheet info
on the Big Three 1 ton HD Diesels.... pending purchase at some
point in the future....

as such, stumbled across this little MPG factoid sheet, and
thought it had some data points worthy of sharing...

enjoy... your mileage may vary.

Charles

from Cummins..... wrote:
Rock-Solid Rules


Every 2% reduction in aerodynamic drag results in approximately 1% improvement in fuel economy

Above 55 mph, each 1 mph increase in vehicle speed decreases fuel economy by 0.1 mpg.

Worn tires provide better fuel economy than new tires, up to 7% better fuel economy.

Used lug drive tires can get up to 0.4 mpg better than new lug tires.

Ribbed tires on the drive axles provide 2–4% better fuel economy than lugged tires.

Every 10 psi that a truck’s tires are underinflated reduces fuel economy by 1%.

The break-in period for tires is between 35,000 and 50,000 miles.

Tires make biggest difference in mpg below around 50 mph; aerodynamics is the most important factor over around 50 mph.

The most efficient drivers get about 30% better fuel economy than the least efficient drivers.

Idle time is costly. Every hour of idle time in a long-haul operation can decrease fuel efficiency by 1%.


Cummins website.....
  • The Cummins site is talking about OTR trucks, not pickups and yes, those tires can see a lot more than 50K miles.
  • Andy,

    Please remember I have nothing to do with the material
    presented... and, can honestly state I did not make a political
    connection... just thought the information worthy of sharing.

    here is a link to the info... I would hope that the Engineers
    at Cummins would have reviewed this before the Marketeers and
    Lawyers, and those interested in Political intrique got hold
    of it...

    the red highlighted sentence is the link.

    Charles
  • well first off the break in period for tires is 50K? Most truck tires will only last 50-60K.

    Under inflated tires decrease fuel economy by 1%, how are you measuring 0.2 MPG?

    and with newer multi-overdrive transmissions traveling above 55MPH doesn't have the same effect on fuel economy it used to.

    Obama made these same suggestions to get us off foreign oil....they laughed him off the stage.
  • Jim,
    You are welcome.

    Andy,
    Thanks for your opinion... specifics please.

    Charles
  • cdlaine wrote:
    Team...

    Just starting to build my own "+/-" database/spreadsheet info
    on the Big Three 1 ton HD Diesels.... pending purchase at some
    point in the future....

    as such, stumbled across this little MPG factoid sheet, and
    thought it had some data points worthy of sharing...

    enjoy... your mileage may vary.

    Charles

    from Cummins..... wrote:
    Rock-Solid Rules


    Every 2% reduction in aerodynamic drag results in approximately 1% improvement in fuel economy

    Above 55 mph, each 1 mph increase in vehicle speed decreases fuel economy by 0.1 mpg.

    Worn tires provide better fuel economy than new tires, up to 7% better fuel economy.

    Used lug drive tires can get up to 0.4 mpg better than new lug tires.

    Ribbed tires on the drive axles provide 2–4% better fuel economy than lugged tires.

    Every 10 psi that a truck’s tires are underinflated reduces fuel economy by 1%.

    The break-in period for tires is between 35,000 and 50,000 miles.

    Tires make biggest difference in mpg below around 50 mph; aerodynamics is the most important factor over around 50 mph.

    The most efficient drivers get about 30% better fuel economy than the least efficient drivers.

    Idle time is costly. Every hour of idle time in a long-haul operation can decrease fuel efficiency by 1%.


    Cummins website.....



    there's so much wrong with this it's not even funny.
  • Hmmm...

    Good posting Charles.
    Somewhat in depth without being difficult to follow or implement.
    Printed this for good reference.

    Again thanx...