Fuel milage on 8.1

tractorsx · December 13, 2005

I have 5500 miles on my 05 Serria CC 4X4 with 8.1. I expected poor fuel economy but this is ridiculous, only getting 8MPG at best around town 11MPG on hi way. Will I see anything better when mileage passes a certain point. I am not wanting to get out of this PU yet but 20+MPG that my son gets out of his Dodge Cummins is starting to look good, and his pulls far better to boot! I can live with not pulling as good but desperately need help on MPG problem, can I expect a noticeable increase some time soon? Thanks for any input.

Trouttrooper · December 13, 2005

Not really, the best you'll probably get is 12 mayyybe 14 mpg. Just have to realize it's a big block gas engine, be thankful that it's better than the 4-5 mpg the old 454's use to get.

3500in nc · December 13, 2005

I have 5500 miles on my 05 Serria CC 4X4 with 8.1. I expected poor fuel economy but this is ridiculous, only getting 8MPG at best around town 11MPG on hi way. Will I see anything better when mileage passes a certain point. I am not wanting to get out of this PU yet but 20+MPG that my son gets out of his Dodge Cummins is starting to look good, and his pulls far better to boot! I can live with not pulling as good but desperately need help on MPG problem, can I expect a noticeable increase some time soon? Thanks for any input.

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sry to say but no that is in the average

now that said there is somthing that can be done about it and that is get a tune and have whoever your tuner is make it more efficent

the 20mpg is good but remember its still out of a dodge lol

tractorsx · December 13, 2005

I have 5500 miles on my 05 Serria CC 4X4 with 8.1. I expected poor fuel economy but this is ridiculous, only getting 8MPG at best around town 11MPG on hi way. Will I see anything better when mileage passes a certain point. I am not wanting to get out of this PU yet but 20+MPG that my son gets out of his Dodge Cummins is starting to look good, and his pulls far better to boot! I can live with not pulling as good but desperately need help on MPG problem, can I expect a noticeable increase some time soon? Thanks for any input.

<{POST_SNAPBACK}>

sry to say but no that is in the average

now that said there is somthing that can be done about it and that is get a tune and have whoever your tuner is make it more efficent

the 20mpg is good but remember its still out of a dodge lol

<{POST_SNAPBACK}>

tractorsx · December 13, 2005

Yea I have watched this forum about tunes but they seem to be very hit and miss about getting better economy, seem to be better at getting more performance. If I could get closer to 12 or 13 around town it would help.

TimTim · December 13, 2005

I have 5500 miles on my 05 Serria CC 4X4 with 8.1. I expected poor fuel economy but this is ridiculous, only getting 8MPG at best around town 11MPG on hi way. Will I see anything better when mileage passes a certain point. I am not wanting to get out of this PU yet but 20+MPG that my son gets out of his Dodge Cummins is starting to look good, and his pulls far better to boot! I can live with not pulling as good but desperately need help on MPG problem, can I expect a noticeable increase some time soon? Thanks for any input.

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Join the crowd, my last tank was the worst since I've had the truck 6.9mpg not hauling or driving it hard. Best I've seen is 9 city 14.4 highway. Can't figure out where the 6.9 came from? It is ridiculous with todays technology that 11-12mpg can't be achieved.

Gary8.1 · December 13, 2005

I have 5500 miles on my 05 Serria CC 4X4 with 8.1. I expected poor fuel economy but this is ridiculous, only getting 8MPG at best around town 11MPG on hi way. Will I see anything better when mileage passes a certain point. I am not wanting to get out of this PU yet but 20+MPG that my son gets out of his Dodge Cummins is starting to look good, and his pulls far better to boot! I can live with not pulling as good but desperately need help on MPG problem, can I expect a noticeable increase some time soon? Thanks for any input.

<{POST_SNAPBACK}>

Join the crowd, my last tank was the worst since I've had the truck 6.9mpg not hauling or driving it hard. Best I've seen is 9 city 14.4 highway. Can't figure out where the 6.9 came from? It is ridiculous with todays technology that 11-12mpg can't be achieved.

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I think it might have something to do with the "winter blend gas" All summer I was getting about 9.5 city and between 13-14 on the highway depending how fast I drive

The last time I filled up, it was 8.25 mpg for all in town driving. I am contributing it to being 10 below zero and the winter blend gas. The one good thing is gas has dropped to $1.93 here, so I am getting a lot more Miles per Dollar

dewfpo · December 13, 2005

My worst has been 10.67 and my best 13.43 with an avg of 12.43 mpg (DIC says 13.1 but it lies) over 4,600 miles on my '05. If I keep it at 65 mph, cruise conrol on, flat highway the 8.1 will get close to 14.7 mpg (by resetting the mpg meter on the DIC).

Winter gas (ethanol) will hurt, as well as warming up the truck in the morning or lots of idling and low tire pressures.

DEWFPO

silverado3500 · December 13, 2005

The winter blend gas/fuel has a lot to do with it. Diesels really take a hit in mileage on the winter blend as well.

tps0424 · December 14, 2005

I thought the 8.1 mileage was supposed to be almost the same as the 6.0? I got 11 or 12 from my 6.0 with 4.10s almost all of the time.

FWIW... my 6.8 V10 is getting 10.7 with 4.30s.

PaulieK · December 14, 2005

Like the old man used to say " Speed cost money, How fast you wanna go?" Personally why on earth would anyone expect an 8.1 to give good mileage? That is like owning a Howitser cannon and then complaining that the thing hurts your ears when it goes *BANG*! If you had been concerned with gas mileage and expense you should of bought a V6 or a 5.3.

SilveradoWV · December 14, 2005

I agree with some of the above posts, anyone in their right mind kinda knows gas mileage is going to suck when you buy one...

Elwood 2000 · December 15, 2005

Tractorsx, I am sad to hear of your poor milage. While the 8.1 shouldn't win any fuel efficiency awards, I have heard a TON of people on this site and others claim 10-11 city and 12-13 highway without towing a load. Hopefully it will get better for you. 10 is a tough pill to swallow, but for the trade off in power, it is to be expected, but 7-8 is just plain lousy.

I have almost decided that my next rig will be a 2500 Suburban with the 8.1, but if real world numbers are 7-8, going with the smaller 6.0 with a tune may be a better option.

N900WM · December 15, 2005

If I could get closer to 12 or 13 around town it would help.

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Will never happen.

Bart2500HD · December 15, 2005

Not really, the best you'll probably get is 12 mayyybe 14 mpg. Just have to realize it's a big block gas engine, be thankful that it's better than the 4-5 mpg the old 454's use to get.

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Putting this in perspective, it's not too bad.

Ditto. I average 8-9 mpg around town and on the highway closer to 13 mpg, unless I'm pulling something. Usually, my truck only leaves town TO PULL SOMETHING, but that's why I bought it.