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Discussion Starter #1
what cause's the such crappy fuel milage on the lly's?
Is it the non efficent restrited vgt turbo's/factory tunning?

Im looking at buying another truck and stuck i wanted to buy another lb7 but everything around me is beat to hell and back really didnt wanna buy another lly because the crappy fuel mpg.
 

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i dont know what you call crappy, me and dad both get like 16.5mpg not pulling.
you want really crappy buy you a 6.4 ford. That they suck diesel
 

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Discussion Starter #3
yeah my 03 lb7 got 25mpg this 14-16mpg is crappy!!!!
 

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mine is city, rural area drivng. You can always do a few mods to help you out. maybe get 18ish out of it. city driven, slapping down 20 in the city i call bs.
 

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LLYs just need a little lovin and they'll be nice lol mine gets 22-23mpg most of the time and I still have factory CAI and the lengendary restrictive MP
 

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I have only had my Duramax for a week and a half but I filled it up last week and drove it down to around half a tank and filled it back up and checked mileage, and it was 17.2.

Now having said that, I was very impressed considering the fact that thats all around town driving and taking a few friends for a ride showing them how much power the Dmax had and basically running the truck pretty hard.

Also mine is a crew cab dually 4x4 and considering I was getting around 14.5 in my old powerstroke, Im very pleased.

I just swapped out the MP with the AFE, so im anxious to see if I cant make it better.

JB
 

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I get 14-16 and I drive like a bat out of hell
 

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i get between 14-16 mpg 50/50 city and highway and i kick the crap out of it alot
 

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13-16 here and I run the crap out of mine. If i drive like and 80 year old man and dont go over 2000 rpms i got 17.5 mpg once but that only happened once in 3 years lol My friend just bought an LLY with 150K on it and he gets 18-19 mpg. I gave up on trying to get better mpg out of mine and bought a 96 honda civic to drive back and forth to work.
 
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See sig, I am happy with the mpg
 

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Mods in sig. I average around 19 running around town. I've seen as high as 23 on the road if I baby it. I'll average around 16 or so if you run it hard around town. Thats all hand calculated too..
 

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I have tagged 24 mpg on the highway if I drive easy....around town around 15/16 If I take it easy towing I can get 14....
 

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17 to 18 in the city, 22 to 23 on the Highway for me. 15 to 16 pulling also with 14 being my lowest ever.
 

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16-18 round town and a couple more on the highway (often riding at the speed governor) I've had it as low as 15 and change, but that was a shit-ton of stop-go and idling. Can't complain one bit on mpg. (Have gotting 30's on highway drafting Semi's but truckers probably don't appreciate that shit, so I did it for a little while, saw it stabalize ~ 36mpg and was happy :thumb)
When I started off, in PA following truck I saw crazy-sweet MPG:
 

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My father in laws 05 never got over 15 but it had a crappy tuner on it. Right now the dealership is putting 4 injectors in it. It was smoking like a brush fire. We will see what it gets with the new injectors and stock tune. Also your tires can make a difference too.
 

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mine is 10-12 towing , in town 16-17 over the road 18-19 all hand cal. and i preaty much check every fill up before any mods 14 around town, 10 towing , 16 over the road no load .mine is a daully
 

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my lb7 in town 15-17 on highway 20 at 65 23 at 55 on winter fuel stock wise havent done it with sumer fuel diablosport on 65 got 21.7 going 70 and 16 in town. EFI high of 18 in town and 17 going 70?? back with diablo and currently running truck stock to see what it does and I like the way it drives stock might just keep it there and say screw mileage its paid for anyway :)
 

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My truck has been kept pretty stock except an 06 kodiak mp. I normally see 16.5 mpg. rural country roads and city traffic mostly. but also long trips I seem to get the same no matter how I drive.

I just ordered two things for the truck. superchips vivid and a mbrp 5inch downpipe back exhaust. will run the vivid by itself with econo tune before installing exhaust and then exhaust with stock tune and then with both. I'm hoping for something close to 20 mpg or better.
 

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my rig is stock 05 and i get 18 to 19 driving to and from work. something like 12 to 14 towing 10000lbs
 

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I just bought my lly a week ago and filled her up last Friday. I pulled a dump trailer about 100 miles, played the red light green light game for over 100 miles and maybe 50 miles on the highway. Stopped Monday morning to fill up for work for the week and hand calculated 18.6 mpg. I was shocked way better than I expected!


Sent from my Autoguide iPhone app
 
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