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Posted

Just put 1,200 miles on... now up to 2,300 or so total...

 

Cruise for most of the trip varying from 74-79 so as not to peg it at any one speed for too long.

 

400 mile average is 15.1 - 'best' is 18.9

 

Questions:

- How is 'best' calculated - I know at a couple points I was getting better than 18.9 for an extended time.

 

- 15.1 at an average of 75 seems really low for a vehicle that's rated at 22 highway - I know its cold and its winter gas, but it shouldn't be knocking that many miles per gallon off, right?

 

My '07 Yukon with 150K on it was running better milage than this truck...not the end of the world, but expected better by now.

The 400 mile is a moving average since you last reset it. If the average is higher than your best, it will bump it up accordingly. While your momentary mileage might be greater than your best, it has to be an accumulative average for 400 miles to make it count. Thus the 25 mile best average will likely be your highest, then the 50, and finally the 400.

Posted

The 3.23 is for the V6.

3.23 is standard for 2wd models. For the V6 and V8. Plenty of people on here have them. Just like you can get the 3.42 on any 4wd regardless of the engine.

Posted

I was getting 18-20 with stock 265/65-18s and V4 was working a lot now I am averaging 15-16 with1000 miles on mine 5.3 3.08 and 275/70-18s which are 1.6" taller than stock 265/65-18s

 

Wondering if calibration is the answer or just waiting for it to warm up it's been 22F or below the last 3 days here.

Running 87 from same station since purchase.

Posted

I only have 400 miles on mine it's about half highway half cityy average is 11.7 it's pretty cold here but I'm surprised it's so low. I swear one of the silverados I test drove had a instant mpg screen and I can't find it on my truck.. Can anyone help?

 

 

Sent from my iPhone using Tapatalk

Posted

My mileage has been in the toilet since its been so cold around here. A lot of long idle remote starts and winter blend combined with sub zero temps....

Posted

I drove to work @30miles this morning it was 12F, got 13.3MPG average for the trip. Drove home same route same traffic but in reverse and it was 45F .... 18.4MPG average.

 

I have a 2012 Acura TL SH-AWD and when I have driven it I am almost the same for MPG on both legs. I am thinking that the Tires have made a slight decrease maybe 1-2MPG it doesn't go into V4 as often as it used to, but that the sub freezing temps are not a friend of the AFM motor. The engineer in me has to know the mechanics behind this.

 

I think I am going to drive it a week or so before I spend @$200 on a programer to recalibrate the computer for the tires or the dealer to recalibrate for the tires.

Posted

I only have 400 miles on mine it's about half highway half cityy average is 11.7 it's pretty cold here but I'm surprised it's so low. I swear one of the silverados I test drove had a instant mpg screen and I can't find it on my truck.. Can anyone help?

 

 

Sent from my iPhone using Tapatalk

You might need to go to the options screen on the DIC to enable it.

Posted

How do you guys calculate it yourself that is more accurate than the computer?

Do you fill it till you can see gas or how do you know exactly how much it used?

I would think the computer would be more accurate.

Posted (edited)
My 2010

 

 

 

 

Ryan

 

Thanks but we are in the 2014 section...

 

Sent from my SCH-I535 using Tapatalk 2

 

Edited by BringTheRain403
Posted

On cold mornings my truck is getting around 15mpg to work. Tire pressure starts at around 32 psi. On the trip back with warmer temps and tire pressure back up to 35-36 I'm getting 18-18.5. Seems like the lower pressure and colder air hurts the mpg a good bit.

 

Also you have to keep in mind I'm running 275 60s without changing the speedo.

Posted

On cold mornings my truck is getting around 15mpg to work. Tire pressure starts at around 32 psi. On the trip back with warmer temps and tire pressure back up to 35-36 I'm getting 18-18.5. Seems like the lower pressure and colder air hurts the mpg a good bit.

 

Also you have to keep in mind I'm running 275 60s without changing the speedo.

I'm running the 275/70-18 BFG which is a 10ply...60psi min, 80psi recommended...pressure doesn't seem to matter 60-80psi fuel mileage is same, with 5.3 it seems to HATE anything below @32F

Posted

Spoke with different dealer from where I bought it, the 2014 is tuned so specifically, oversized tires SCREW up the AFM....

 

Bummer.

Posted

Spoke with different dealer from where I bought it, the 2014 is tuned so specifically, oversized tires SCREW up the AFM.... Bummer.

Easy to correct with a Hypertech speedometer calibrator.

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