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Posted

Hi everyone! I'm new to the forum and I'm about to order a new 2014 Sierra. What's everyone that's lucky enough to own one seeing in the fuel mileage dept? I'm particularly interested in the city mileage since I have about a 4 mile drive to work and don't do much highway driving. I have a Trailblazer SS currently and I'm getting about 11 MPG. Hoping for a decent improvement and to get at least what the EPA rating is for city driving (16 MPG). However, I know the EPA estimates aren't always the most accurate. Thanks in advance!

Posted

609 miles on odometer (about 200 hwy, 400 city) & DIC shows 16 MPG average (that's with AT tires, level, & front air dam removed)

Posted
I personally would like to know what the highway economy is like, I do about a 1000 miles a week almost all highway

 

Holy crap! :blink:

 

Sent from my SCH-I535 using Tapatalk 2

 

 

  • Like 1
Posted

I personally would like to know what the highway economy is like, I do about a 1000 miles a week almost all highway

 

I bought my truck & then drove about 200 miles of interstate to get home. I averaged 21-22 MPG, going 77 MPH, with an outside temp between 85-90 degrees.

Posted

Thanks Motomedic, that's the kind of real world numbers I was hoping for

Those #'s are from 2WD with the factory "nose dive" angle. If you really wanted to squeeze every MPG out of her you could drop the rear a tad, add a bed cover, and even go so far as the adding close out panels under the truck (simple thin sheets of aluminum mounted similar to skid plates but the full length of truck frame). Though depending on how you use your truck, those might be unrealistic.

Posted (edited)

I was quite surprised by the AFM fuel mileage program in this EcoTech 5.3L. it will really help this trucks fuel mileage I was seeing 20-21.9 at a highway speed of 60-70 mph of a mix of rolling hills and bridges.The test drive was on the 2014 Chevy Silverado 1500,4wd,5.3L,3:42,standard bed and I know a lot has been said that DIC fuel mileage systems are not accurate,but this software tends to tell a different story,of being very close on estimates,EPA new rating system has been very close on cars and trucks this year across the board a mix of real and track roads(I see them from time to time in LA here cruising are freeway systems heavy traffic and wide open interstates.In the end I have decided to buy a 2014 Chevrolet Silverado 1500 LTZ,Z71,6.2L,3:73,Max trailer packaged truck.This is a fair stone's throw ahead of my current pickup,performance.The 5.3L was very responsive to throttle and would run up or down the gears in nano seconds,without me even looking down,I would not know it because the linear shift response was quite sharp.This truck was all about fuel mileage this incoming Gen powertrain is a very big jump for GM. The E85 fuel hp/torque figures' were impressive.A very light 1/2 ton truck and very responsive with the electronic steering at the helm moving within the lane is all about eliminated this was running 265/55/20's.They say that GM will release a 5.3L Max Trailer tow which will include the 3:73 axle for this truck that would hit mileage a tad but performance will put a smile on any Silverado owners face that I know.So I wait for the ordering giants at the General to load the 6.2L option and all the goodies that make this truck again in my book a world class truck along side it's big brother the Chevrolet Silverado 2500/3500 Duramax diesels.

Edited by Bravo1
  • Like 1
Posted

On my way to New Orleans, I decided to check how much my modifications had decreased my MPG. The big three I did that affect gas mileage are removing front air damn, raising front end 2", and installing larger tires. (the numbers below for Modded Truck have been corrected for increase in tire circumference)

 

Stock truck: 21+ MPG @ 77 MPH (outside temp 85-90 degrees)

Modded truck: 18 MPG @ 77 MPH (outside temp 90-95 degrees)

 

So my modifications cost me 3 to 4 MPG at interstate speeds. Well worth it to me! :thumbs:

  • Like 1
Posted

I personally would like to know what the highway economy is like, I do about a 1000 miles a week almost all highway

i do anywhere from 600 to 1000 a week... i have car that i use as my DD... the money i save in fuel pays for the car.. i get about 40mpg on the highway

Posted

On my way to New Orleans, I decided to check how much my modifications had decreased my MPG. The big three I did that affect gas mileage are removing front air damn, raising front end 2", and installing larger tires. (the numbers below for Modded Truck have been corrected for increase in tire circumference)

 

Stock truck: 21+ MPG @ 77 MPH (outside temp 85-90 degrees)

Modded truck: 18 MPG @ 77 MPH (outside temp 90-95 degrees)

 

So my modifications cost me 3 to 4 MPG at interstate speeds. Well worth it to me! :thumbs:

 

Would think most of the loss is from the tires?? Did you use the DIC for the #s and/or check it at the pump?

Posted

i have 1300 miles on my 4X4 LTZ Z71 5.3L, i have a 15 mile highway drive to work with a stop about every 2 miles i drive, if I baby it I get over 20MPG. The DIC has an MPG readout for every 25, 50, or 400 with your average and best mileage reading, my best 25 miles MPG is over 26, don't know how this figures but it sure sounds good. Use to have an 09 Acadia which i never got anything better than 21MPG highway.

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