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Changing differential gears to improve mileage

Discussion in 'General Tundra Discussion' started by C-tundra, Sep 8, 2016.

  1. Sep 8, 2016 at 1:47 PM
    #1
    C-tundra

    C-tundra [OP] New Member

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    Howdy from N. C. just wondering if anybody has ever changed differential gears to get better fuel mileage, mine has the 4.30 and so far I'm getting 16.2 mpg. A friends dad just bought a dodge with the same engine and he's getting over 20 mpg. the only difference we can see is in the differential gearing
     
    Filthyphil likes this.
  2. Sep 8, 2016 at 1:57 PM
    #2
    Ryan Mc.

    Ryan Mc. New Member

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    Dodge and Toyota don't share the same engines from factory. They may have the same displacement (5.7L) but that's comparing apples to oranges. You also need to take into consideration the transmission, aerodynamics, tire heights, rolling resistance, people's driving habits, etc...

    My opinion, if mpg was a big issue with the Tundra, why buy one? And 16.2 in my book is pretty damn good. I drive a lot of streets (currently) averaging about 12ish.
     
  3. Sep 8, 2016 at 5:06 PM
    #3
    ColoradoTJ

    ColoradoTJ Certified tow LEO Staff Member

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    The differences is an 8 speed transmission.

    Towing and 4.30 gearing is pretty good. Yesterday I could have used 5.13 gears going over Vail Pass in Colorado. My fuel pedal was matted.
     
  4. Sep 8, 2016 at 7:07 PM
    #4
    zcarpenter92

    zcarpenter92 Yotas and Yellow Jackets

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    Pretty much sums up my thoughts. Anyone complaining about "bad" gas mileage in a pickup gets very little sympathy from me.
     
  5. Sep 8, 2016 at 7:39 PM
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    ColoradoTJ

    ColoradoTJ Certified tow LEO Staff Member

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    Yep. You start complaining, go get a diesel.

    These guys did 10.5 mpg with a 15k lb load behind them all the way from NC.
    image.jpg
     
  6. Sep 8, 2016 at 9:24 PM
    #6
    trayday

    trayday New Member

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    Dodge also uses twice as many spark plugs as toyota for an increase in fuel economy.
     
  7. Sep 8, 2016 at 9:36 PM
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    ColoradoTJ

    ColoradoTJ Certified tow LEO Staff Member

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    Ram does use more spark plugs, but that is a losing argument since the cost of changing out 16 vs 8 spark plugs way out weighs the 3000.00 in fuel savings in 100k mile change out intervals.
     
  8. Sep 9, 2016 at 5:42 AM
    #8
    C-tundra

    C-tundra [OP] New Member

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    So I'm guessing the answer to the actual question is no, nobody has ever changed the gears in the differential for better fuel mileage
     
    Filthyphil and Hammerhead like this.
  9. Sep 9, 2016 at 5:58 AM
    #9
    ShreveportTSS

    ShreveportTSS Huh?

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    Probably not as a sole purpose. You have to watch gear changes as going up or down may have the opposite effect you are looking for. Your driving needs/habits may require a lower gear to get an increase in mileage. I had two chevy trucks with the same engine and tranny. One had the 3:73 gear the other had the 3:23. The 3:73 gear got 24mpg average and the 3:23 was a slow POS that got 17mpg. The engine had to work harder to do the same work even down here where it's flat.
     
    Ancient1 likes this.
  10. Sep 9, 2016 at 8:15 AM
    #10
    BlueFalconActual

    BlueFalconActual Field Day Inspector Extraordinaire

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    Can it be done? Im sure it can but the reason why none of us so far have seen it done is probably because it isn't worth it. It's more than gearing that make the Ram get 20mpg. Tundras are generally heavier and higher than the other 1/2 tons.

    I get 19-20 mpg on the highway going 65 and 18-19 going 70-75. 1-2 mpg loss compared to the Ram will be a drop in the bucket monetarily when it's time to trade in or sell.
     
    dino112265 and 831Tun like this.
  11. Sep 9, 2016 at 8:26 AM
    #11
    TNTundra08

    TNTundra08 New Member

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    Shit, I get 10-11 mpg just driving around town not towing. I'll trade ya.
     
  12. Sep 9, 2016 at 8:27 AM
    #12
    Mike

    Mike Tread lightly.

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    yep bank account is running low from it..
    If you want to get better MPG...

    Keep your foot off the fuel.. no heavy foot.

    Keep tires pressure at correct psi.

    Keep maintenance up..

    It's a damn truck what do you want Prius mpg? Tundra is a heavy truck..

    Get a scangauge or ultragauge and change your driving habits as it will show mpg..
     
    dino112265 and zcarpenter92 like this.
  13. Sep 9, 2016 at 10:01 AM
    #13
    TNTundra08

    TNTundra08 New Member

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    If you weren't meant to have a heavy foot, God wouldn't have created torque. Smiles per gallon > miles per gallon
     
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  14. Sep 9, 2016 at 12:49 PM
    #14
    RLHULK

    RLHULK Too many gamma rays in all that BBQ smoke.

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    In 1989 I purchased a flame red 1989 GMC SIERRA SLT step bed with a 350, auto and 2:73 rear end...not a good puller but damn did I get gas mileage on the highway...guess someone could change the gearing in a Tundra to 2:73 and see what happens...

    Got a couple pics, First is the GMC, second is a 79 Jeep CJ5 I had at the same time, cause I had to have a 4wd, and I am redneck. These were taken 26 years ago..now I am sad cause I really mis that Jeep, money pit that it was...

    89gmc.jpg 79jeep.jpg
     
    Last edited: Sep 9, 2016

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