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Discussion Starter · #1 ·
I recently bought this 2010 ecsb 4wd with 5.3 and 3:08 gears. Wasn't my first choice as far as 3:08 gears but the deal was good. My driving every day consist of a 14 mile round trip to work with one red light and two 4 way stops. I drive normal and I have hand calculated it several times to always come up with 11. 2 to 12.4 mpg. Is these 3:08's the reason or is something wrong? I want to upgrade to 33's but then I'm gonna probably be in big block mpg range. My 98 5.7 averaged around 14. I did take a trip to the mountains and filled up before getting on the interstate and then when I got to my exit I filled back up. I run the piss out of it with constant downshifting to maintain speed even on the slightest hills and had a hand calculated average of 18.7. Is the gear swap gonna be my best bet for my daily commute?
 

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I average 15-16 with the same truck and 3.42 ratio in town. On the freeway around 20. I have 18x9 wheels with 285's. You must have a lead foot:crazy:


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Discussion Starter · #3 ·
I average 15-16 with the same truck and 3.42 ratio in town. On the freeway around 20. I have 18x9 wheels with 285's. You must have a lead foot:crazy:


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I would love to get 15-16! I drive like a grandpa and still the same.
 

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My DIC right now says my in town is 16.3. Haven't been on the freeway in a while. Can't go off that for an exact number though. I do have autocal without v4 mode.


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Discussion Starter · #5 ·
My first step is gonna be a tune and I will see what that does. My service truck is a 2005 6.0 with 4:10's and I drive the wheels off it and get 14.
 

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11.2 - 12.4 is a very low average for your truck. Especially considering that it is AFM equipped. You should be closer to 15 mpg all day long.

I average 14-16 out of my 2003 ECSB Z71 with 285/75 Toyo MT's. It's leveled, has a CAI, and exhaust. 3.73 factory gearing.

My leveled 2014 Z71 CCSB on factory wheels and tires with a Flowmaster Delta 50 is averaging 21 mpg thusfar (only 1600 on the truck)... It is equipped with 3.73's as well I believe. Would have to double check...
 

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Dbl post...
 

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Discussion Starter · #8 ·
After doing all kinds of research reading old posts I feel that disabling AFM needs to be my first approach. I noticed yesterday that when driving with just minimal throttle pressure it accelerates nicely through 1st-2nd but when it hits 3rd with same pressure it goes to turd mode. Gears will definitely be my next approach for my rural driving. Then I get to go through the same dilemma I did with a mustang a few years back .. 3:73 or 4:10? Thanks for the replies!
 

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3.73 if sticking with the same tires, 4.10 if you're moving up to 33s
 
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