Fuel Economy Advice

[Sergio15]

Hello I’m new to this Forum and I just bought a 2016 GMC Sierra Denali with the 6.2 and 8 speed transmission. It has 135,000 kms on it and I was wondering if there is anything I should do to get better fuel mileage from this truck I’m pretty sure the previous owners were running 87 or 89. I have ran two tanks of 91 but I find the fuel mileage isn’t that great. It’s mostly city driving so far. Should I do a Seafoam cleaning in the tank and vacuum? Should I run a certain style of plugs? What are your thoughts on programmers and cold air intakes? Eventually gonna do an exhaust system as well what kits are best suited for this truck?  Just got the truck a few weeks ago and looking to improve the truck. It’s my first GMC I’ve always been a GM fan my dad always had them growing up so just looking to make this truck better! Thanks for any advice.

[Mozzer]

. I have ran two tanks of 91 but I find the fuel mileage isn’t that great. It’s mostly city .

Welcome.

What mpg are you actually getting, city driving is going to be a struggle to improve with anything other than driving habits I would think.

2014, 5.3, 4x4, work truck

[Sergio15]

Thanks, so far with 170 kms on the tank with a few times in 4x4 because of winter driving conditions for maybe 40 kms. I’m at 21L/100 right now. It has been mostly residential driving stop and go. I am just wondering if it’s a normal number or is there something I can do to improve the numbers. I don’t drive the truck hard as much as I would like to open it up like when I was younger... but I’m driving it responsibly. Thanks for responding 

[JimCost2014]

32 minutes ago, Sergio15 said:

Hello I’m new to this Forum and I just bought a 2016 GMC Sierra Denali with the 6.2 and 8 speed transmission. It has 135,000 kms on it and I was wondering if there is anything I should do to get better fuel mileage from this truck I’m pretty sure the previous owners were running 87 or 89. I have ran two tanks of 91 but I find the fuel mileage isn’t that great. It’s mostly city driving so far. Should I do a Seafoam cleaning in the tank and vacuum? Should I run a certain style of plugs? What are your thoughts on programmers and cold air intakes? Eventually gonna do an exhaust system as well what kits are best suited for this truck?  Just got the truck a few weeks ago and looking to improve the truck. It’s my first GMC I’ve always been a GM fan my dad always had them growing up so just looking to make this truck better! Thanks for any advice.

Welcome to the site.

 

You bought a truck (1500) with the biggest engine available, what are your expectations?

 

Around town this time of year, it is not good with winter blend gas being used, maybe 12.0 - 14.00 mpg. Freeway, 20.00 - 23.00 is realistic.

 

If you have a heavy right foot, you will never get anything close to what you want. Just enjoy the truck, you made the right choice with the package you bought.

 

Use 91 or higher octane, the engines are tuned from the factory to utilize that grade of gas.

You paid for 420 HP,  lower octane reduces the power by retarding the timing.

[Sergio15]

Yeah I knew I wasn’t buying a fuel saver with that power I guess I’m not used to the numbers yet. I was just curious about anything I could do to get better numbers.

[Mozzer]

Thanks, so far with 170 kms on the tank with a few times in 4x4 because of winter driving conditions for maybe 40 kms. I’m at 21L/100 right now. It has been mostly residential driving stop and go. I am just wondering if it’s a normal number or is there something I can do to improve the numbers. I don’t drive the truck hard as much as I would like to open it up like when I was younger... but I’m driving it responsibly. Thanks for responding 

Your doing ok for stop & go driving, I'm getting around 19 l/100 kms with a mix of 20 minute trip to work on rural roads & some stop & go, that is with a 5.3 six speed & some in 4x4. I get up to around 12 l/100 kms on a highway trip.

Enjoy.

2014, 5.3, 4x4, work truck

[JimCost2014]

15 hours ago, Sergio15 said:

Yeah I knew I wasn’t buying a fuel saver with that power I guess I’m not used to the numbers yet. I was just curious about anything I could do to get better numbers.

Drive with your left foot, you will be forced to stay out of the throttle.....

 

Your mileage will improve with spring and summer gas, and as you get accustomed to the truck, they are tuned for maximum mileage from the factory.

There are some aftermarket parts/mods that will help, just do your research.

[03dyna]

Hi just wondering if you are using the remote start a lot of idling will bring down your fuel mileage really quick. 

[Sergio15]

I have been using the remote start, makes sense that it would elevate those numbers. On my next tank I will try not using it and compare the numbers. Thanks

[03dyna]

i know on mine when it is -20 and I let it run for at least 10 min before I drive I see  21L/100 quite regularly .But in the summer when I jump in and go I usually see around  11L/100 . 

[Sergio15]

Right on yeah the beginning of this tank was in the -20 range so makes sense. Thanks for all the info

[AdioSS]

Is the AFM working? What make, model, & size tires does it have? Do you have a bed cover?

[Sergio15]

I bought the truck used from a dealer and they did their full inspection on it so I assume the AFM is working. It does go from 4-8 on the indicator. I run 275/55R20 tires and yes it came with a bed cover.