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Old 12-06-2017, 03:34 PM   #1
bluec10
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Question Poor Fuel Economy - Advice?

Need some advice - I'm getting an average of 13 mpg out of my 2005 GMC Sierra 4x4 with a 4.8L. Truck has 156,000 miles on it. I live in Canada so it's winter right now but the mileage seems pretty low.

Any advice about what helps improve mileage in these trucks? Is this the kind of mileage that others are getting?
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Old 12-06-2017, 05:57 PM   #2
GASoline71
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Re: Poor Fuel Economy - Advice?

I'd say you're as close to the best you can get now. My '06 K2500 Silverado gets maybe 12mpg downhill with the wind at my back and I have a 6.0L. A heavy 4x4 with a 4.8L has to work a bit.

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Old 12-07-2017, 11:46 AM   #3
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Re: Poor Fuel Economy - Advice?

My Yukon weighs about 6700 lbs, and with the 5.3 I get around 15-16, but can do a bit better. I've got pretty low rear gears, so my worst mpg is the 10-35mph stop n go stuff. 40+ cruising and it improves drastically.

The stock intake and exhaust system is pretty restrictive, so there are mpg and power gains available there (but the cost doesn't always offset the mpg difference).
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Old 12-08-2017, 02:54 PM   #4
68Gold/white
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Re: Poor Fuel Economy - Advice?

You need to find someone that can alter the factory tune settings. I talked to my buddy's son about one of the programmers for a friends pickup. He said he didn't think much of them, a proper tune would likely yield better results, especially for the $$$. Diablo Motorsports was the name of the programmer I believe. My buddies 2008 5.3 4 door 2WD gets 17 MPG, he was hoping for better. He has not yet done anything.....
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Old 12-10-2017, 02:17 PM   #5
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Re: Poor Fuel Economy - Advice?

I live in Canada my 2005 GMc with a 6.0 eats gas in winter 24 to 100liters all the time
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Old 01-06-2018, 09:57 AM   #6
Burbnasty
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Re: Poor Fuel Economy - Advice?

My wife's 2005 gmc Yukon, my 2500 hd, and our old 2005 gmc all seem to get horrible mileage in the winter.
13 mpg is not bad for the cold months at all, that's about what I average over all.
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