Gear ratio to hit 20 mpg or close HWY 01 Yukon XL

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LordWayback

LordWayback

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A GMT800 isn't gonna get 18mpg, no way, no how.

A 900 might have a shot with newer engine cals, AFM, the 3.08 rear and the six speed.

Tires make a huge difference. You want a rock-hard compound in a highway tire. I know my Goodyear Duratracs might be costing me as much as 2 MPG.
4lslippy bad plugs low miles, factory gears with tons of junk 13.5 it’s insane
 

TollKeeper

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Why would it make it worse I drive over 60 miles a day on a bad day all freeway minus like 4 miles city the city mileage would tank but over the 50+ other freeway miles it’d make a difference?
Lower gears will hurt your city MPG, and help your highway MPG. You have to use more energy to get to the same speed from a stop as its harder to get a lower gear turning. This was overcame in the latter years with more gears in the tranny to offset.

I think I am saying that right.
 
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LordWayback

LordWayback

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Lower gears will hurt your city MPG, and help your highway MPG. You have to use more energy to get to the same speed from a stop as its harder to get a lower gear turning. This was overcame in the latter years with more gears in the tranny to offset.

I think I am saying that right.
I’m not gonna be doing nearly any more city driving , **** these coworkers. He refused to come in and help me so no more rides for his druggie ass. **** city all I’m gonna do anymore is like 2 miles max a day rest will be highway 40-90+ miles. I need the MPG I might switch jobs so its gonna be a gamble if I need a truck.
 

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RST Dana

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Drive 50 mph on flat highways and you might get there.
 
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LordWayback

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What? I man ALWAYS needs a truck! LOL

Reduced fuel economy is the price we pay for safety. All of my family members have been seriously injured in small cars.
$1000 a month in truck expenses before maintenance isn’t a good idea o with how much I’ll be making less going to school
 

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