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I have an 04 LB7, i bought the banks sitnger system came with exhaust, tuner, air box and wastegate actuator. Im getting 15 to 16mpg around town not driving crazy or pulling any wieght, what can i do to get better fuel economy? It might all be bs but i have talked to people with the same rig as me and they are saying the get 19 to 23 mpg town/freeway.
 

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Well first of all, welcome to the forum!!! Is that hand calculated? The dash will lie sometimes and say you are getting better/worse than you really are. Second, when did you last change your fuel filter? Third, run some 2 stroke oil in at every fill up, its getting me better mpg
 

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Rode the Short Bus
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Welcome to the forum.

I would say 19-23 is a bit of a stretch probably.

As was already mentioned, check your maintenance, oil, fuel filter, tranny fluid and filter.

What mods do you have?

When my truck was stock I got about 15.5 mpg. I cut out the muffler and went straight pipe, and I did the Kennedy air box mod. I think both helped.

Now I have a programmer set to +65 hp and have seen my mileage about 17.5 mpg.
 

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Discussion Starter #4
Thanks, Yes its hand calculated the dash is usually 1 to 2 mpg off. I just changed the fuel filter two weeks ago along with the water seperator. Are you saying put some 2 stroke oil in the fuel? if so how much shoud i put in, thats not going to mess anything up internally?
 

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Discussion Starter #5
the only mods i have are the exhaust, intake and banks tuner
 

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Thanks, Yes its hand calculated the dash is usually 1 to 2 mpg off. I just changed the fuel filter two weeks ago along with the water seperator. Are you saying put some 2 stroke oil in the fuel? if so how much shoud i put in, thats not going to mess anything up internally?
Nope it won't hurt a bit, it will actually help lubricate. Many members here do it, along with big rig drivers. Just go to wal-mart and buy TCW-3 rated 2 stroke oil, I buy 16 oz. bottles at a time, and use half of that at every fill up. So 1 bottle lasts me 2 tanks. And the 16 oz. runs maybe $3.
 

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I get anywhere from 14-24 depending on terrain and driving habits
 

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Used to get 17 mpg on a good day stock. Now with EGR deleted, Kennedy air box mod, banks exhaust turbo back, EFI live tuning by Idaho Rob, 5 to 6 speed tranny conversion (about 1mpg increase average), intake horn mod, stock tire size, nicktane prefilter, and lift pump, I can now get 20-21 where I could only get 17-18 before.
As far as 2-cycle oil is concerned, I never ran it with my first set of injectors...only some stanadyne...and got 112K miles out of them. On the 2nd set I ran 2 cycle oil in every tank and only got 56K out of them. For the 3rd set I am not running any 2 cycle oil but running stanadyne in every tank. Personally I think running 2cycle oil, at least for me, was a waste of money and time and seemingly did nothing to extend the life of my injectors. The truck currently has never run so well.
 

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Used to get 17 mpg on a good day stock. Now with EGR deleted, Kennedy air box mod, banks exhaust turbo back, EFI live tuning by Idaho Rob, 5 to 6 speed tranny conversion (about 1mpg increase average), intake horn mod, stock tire size, nicktane prefilter, and lift pump, I can now get 20-21 where I could only get 17-18 before.
As far as 2-cycle oil is concerned, I never ran it with my first set of injectors...only some stanadyne...and got 112K miles out of them. On the 2nd set I ran 2 cycle oil in every tank and only got 56K out of them. For the 3rd set I am not running any 2 cycle oil but running stanadyne in every tank. Personally I think running 2cycle oil, at least for me, was a waste of money and time and seemingly did nothing to extend the life of my injectors. The truck currently has never run so well.
Its a hit or miss. Basically its just what you prefer. With my old 01 I used Power Service and liked it. This 02 Im using 2 stroke oil and it seems to be getting me better mpg. Alot of factors go into this though, my tires are completely different and a little smaller, this truck has less miles, etc.
 

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My old LB7 had no problem hitting 23 mpg, if it was all highway. No way mine would have hit a 23 average city/highway. Easy acceleration, and driving at about 69-70 mph was about perfect for me. Once stop and go traffic was added to the mix, I would average more like 17 mpg or so. All hand calculated.
 

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I just filled up mine last night. All city driving...18.7 MPG, hand calculated. I do try to coast up to a lot of the stop lights around here though. You can see my mods in my sig below.
 

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I would say 19-23 is a bit of a stretch probably.
I don't know about that...maybe let off the skinny pedal a bit and you could see some better mileage. I have 4" exhaust, intake, and programmer and i get 22mpg on the freeway and 19mpg in town. I had a hard time believing that i was getting that good of mileage, so i did it by hand. I still didn't believe it, so i used my gps to keep track of my traveled miles, then did it by hand again. It may also help that i haven't lifted my truck, and i have the stock tire size also.

On the freeway i cruise @ 70mph and average 22mpg.

In town I take it easy, and keep my foot on the shallow side, and get 19mpg.

Maybe my pickup is just a freak of nature, but i don't think that's a stretch.
 

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I get 16-17 with my mods. Depends alot on driving style. but i think you should be getting more out of your setup.
 

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Speaking of runnin 2 cycle oil, anyone on here tried transmission fluid in a tank. A buddy of mine drives a long distance rig puts tranny fluid in every tank and swears by it. Just asking not trying to hijack the thread.
 

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Discussion Starter #15
im getting the feeling after doing some research on the web that my injectors are toast, or are about to be. Last summer i had my fuel pressure regulator replaced because at an idle i would go from about 700rpm to close to 1300 or 1400. Now when its hot out, maby 75 or 80 outside it takes two or three good tries to get the engine to crank over and start. I think they may have been messed up but within the parameters to not get replaced when i got the fuel pressure regulator was changed out but since GM dealerships are out to make money not help the consumer out, now i cant start my truck every time.

Any input form anybody on this, its just a thought i had
 

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The Good Son!
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I had a 2001 LB7, 4x4, ext cab, lwb and I got 17mpg city, 19.5mpg highway driving it hard. All completely stock.

My mileage went down with programmer and bigger tires (285's) around 15mpg city and 17mpg highway.
 

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im getting the feeling after doing some research on the web that my injectors are toast, or are about to be. Last summer i had my fuel pressure regulator replaced because at an idle i would go from about 700rpm to close to 1300 or 1400. Now when its hot out, maby 75 or 80 outside it takes two or three good tries to get the engine to crank over and start. I think they may have been messed up but within the parameters to not get replaced when i got the fuel pressure regulator was changed out but since GM dealerships are out to make money not help the consumer out, now i cant start my truck every time.

Any input form anybody on this, its just a thought i had
Could be alot of things contributing to hard starting. Search around on here on injectors, theres plenty of threads about it. It will save us alot of typing
 

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I'm no expert on tranny fluid, but I do know it has friction modifiers in it. I honestly cant see how it could be a good thing to add to our ulsd, which is already lacking in the lubricity department. JMO though.
 

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when i had my tune i got about 18 city. never above 2000 rpms tho. now that im stock and using opti lube every tank im getting around 16-16.5 city. nicks tune made a world of differnece.
 
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