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V-6 horrible fuel mileage

pottercon

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pottercon Enthusiast

pottercon

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I completely agree it's the style of driving but I would think it would get 15 not 13.5 and like I said the first tank of 13.5 was 140 miles of highway on a 390 mile tank

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KARNUT Senior Enthusiast

KARNUT

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When I was still working I drove 12 miles each way. Some at 45 mph some at 60 mph, medium lead foot. My average mpg with a 5.3, 4 door was 15 mpg on E85.

 

 

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pottercon Enthusiast

pottercon

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With this thread supposed to be about the V-6. I just will be driving a 5.3 as to the V-6 if this is as good as it gets! I do use the low-grade, I believe what is it, 87 octane.

crafferty Senior Enthusiast

crafferty

Posted
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Bought a 2014 v6 Sierra reg cab long bed work truck. Has less than 9000 miles. Bought it to save wear and tear on the big duramax beating around town. Would assume it would get between 18-24 like gm says it should. I have averaged 13.5 mpg on the last four tanks of fuel. I just well be driving a 3/4 6.0... What is everyone else getting in town and or combined?

If your getting 13.5 mpg then your city driving must have lots of stop and go like mine does. For example my city driving in Tuscaloosa yields about 12-14mpg but this past weekend on my hunting trip I averaged about 16mpg and includes using 4hi offroad on the trails to the dove field. But the big difference I saw is that I didn't have all the stop and go either.

NitroDatsik Senior Enthusiast

NitroDatsik

Posted
Posted

I completely agree it's the style of driving but I would think it would get 15 not 13.5 and like I said the first tank of 13.5 was 140 miles of highway on a 390 mile tank

How's is this possible? If you say it was a 390 tank, let's say you pumped the max gallons 26. That's equal to 15mpg. Maybe your little screen doesn't calculate correctly. Do the math next time you pump. Fill up to full, erase trip miles and empty the tank, fill up and how ever many miles your trip says divided by gallons will give you your mpg. I only trust this method

 

2014 Silverado 2WT CC Summit White 4.3L V6

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tnchevy Senior Enthusiast

tnchevy

Posted
Posted

I second that. My truck is almost always .8 mpg higher on the DIC than it is by hand calculating. The other two vehicles in my driveway are about 1.5 mpg on the high side compared to hand calculating so it could be possible that yours is doing the opposite and showing lower mpg's than you are really getting. I have not reset my trip 2 since I bought my truck and after 1 year and 7k miles it says I am at 19.7 mpg but my spreadsheet shows me at 18.94 mpg's.

fondupot Senior Enthusiast

fondupot

Posted
Posted

I second that. My truck is almost always .8 mpg higher on the DIC than it is by hand calculating. The other two vehicles in my driveway are about 1.5 mpg on the high side compared to hand calculating so it could be possible that yours is doing the opposite and showing lower mpg's than you are really getting. I have not reset my trip 2 since I bought my truck and after 1 year and 7k miles it says I am at 19.7 mpg but my spreadsheet shows me at 18.94 mpg's.

 

Yea my truck usually is .5-.8 mpg higher on the DIC page compared to hand calculated averages. Every car with a DIC average has been similar.

ember1205 Senior Enthusiast

ember1205

Posted
Posted

DIC definitely reads high. I use Fuelly for a much more accurate tracking.

 

Know someone with a 6cyl DC. I had the exact same truck with the 5.3, and now have a CC 5.3 (same wheelbase). I get better mileage than he does because of driving style (he pushes harder on the highway than I do).

ember1205 Senior Enthusiast

ember1205

Posted
Posted

Your terrain will come into play as well... In the Northeast, our MPGs seldom generally hit the EPA numbers because it's hilly terrain with lots of stop-and-go in town before you can GET to a bigger road.

SouthpawHD Enthusiast

SouthpawHD

Posted
Posted

My driving style is the truck is, my ign Start 20 times per day. Mostly all in town small town driving! It's a white V6 long bed so I am not hot roding around, I'm working, making trips to the lumberyard etc. it is not loaded down with weight. I pull a zero turn around for a couple miles on Sunday. Very light trailer!. The first tank of gas that got 13.5 included 140 mile trip on the highway. The last 120 mile trip on the highway I noted 20 miles per gallon on the DIC. A tank of gas many last me two weeks, so that's a lot of taking off from a stop over those two weeks. When got the truck with 7500 miles it showed an average of 14.5, I believe, on the DIC. The truck is a theft recovery, so maybe it's still recovering from having the crap drove out of it!..lol

 

Making a ton of small trips simply just reduces the fuel mileage. Plain and simple. No need to look further.

 

And you are making trips to lumber yard, and while not "loaded down", you gotta be adding a bunch of weight too and that will also reduce your mileage.

NitroDatsik Senior Enthusiast

NitroDatsik

Posted
Posted

What rear end does the truck have in it? That could be part of the issue, too.

If I'm not mistaken all 4.3 have the 3.23

 

2014 Silverado 2WT CC Summit White 4.3L V6

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IG: jorge_dropkick_rangel

Brian S. Enthusiast

Brian S.

Posted
Posted

"If I'm not mistaken all 4.3 have the 3.23

 

You are mistaken. I had a 2014 4.3l double cab 4wd with 3.42s.

 

I got 17.6 on my last 2200 combined miles. I used to get 15-16 around town, 20-24 on the highway.

 

Now I have a 2015 5.3l with 3.42s and get about 16 on average combined and 18-20 highway.

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