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Going to be heading to Charlotte, NC this saturday. Gonna be about a 2000mi round trip when all is said and done. Wanting to get the best mileage possible. Right now i just have it on the stock no DPF cause i tow between 14k and 20k everyday, but was wondering if there was a better tune for more MPG, only going to be pulling a light 6x12 trailer to charlotte.
 

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Not sure about the LMM, but my LBZ with the Quad on 90hp......no lie....averaged a hand calculated 26 mpg from eastern NC, to Tennessee back before Christmas. I tracked the miles via GPS and the odometer (which are now identical) divided by the gallons put in and came up with 25.8 mpg at an average speed of about 70 mph. Had my wife look at the GPS and calculate it herself to double check me and she got the same thing. Filled up right as we were leaving, then didn't have to stop for a while. Went 452 miles before I decided to stop and fill up and only put 17.5 gallons in the tank. My fuel needle gets down close to the E mark when I've only burned about 18-19 gallons and at that point I usually fill up just so I don't have to worry about it. I know the tank is 26 gallons, but I've never had to put more than 21 gallons in it.

I thought it was wrong to start with, but I re-checked it on the way home (filled up as I was leaving TN) and went 430 miles before the wife had to use the bathroom....and filled up again there while I was at the station. Had driven 430 miles, and only put 17 gals in this time too which came out to just over 25 mpg. Again at an average speed of about 70 mph.

Now I wasn't towing anything and cruise control didn't come off the whole time. Not sure if 90 hp is the best fuel economy tune but it sure has netted some good MPG's for my truck.
 

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I had mine. It does matter about towing. I would say if all stock and DPF is gone don't be scared of the 70HP tune. If you have the transgo JR you can use the 90HP. I loved the 90, great power yet killer mileage. All honestly I think the 70HP had better mileage both town and highway when I used it. By like1-2 miles easy. Mainly just keep you eye on the temps. If your EGT's are ok you'll be fine you know you just have to back off a bit somewhere. I towed like 4K or so with it on 70 and it wanted to put my EGT's up fast, so makes you just start at that gauge instead of drive. If its a light trailer I say 50HP is a little extra HP and will deff help your mileage out. Eitherway just really keep your eye on that EGT setup and don't beat on it. its not much power but your tranny doesn't know what its like yet.

Also with those tunes I like to put the tranny in "M" and most highway use leave it on 5th gear. 6th sucks I think. Unless your doin a downhill and lookin to coast hit it up a gear. Otherwise 5th got me way better mileage not chugging and really helps keeping temps down.
 

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Discussion Starter #7
isnt the first level on quad called economy?
Yea there is an economy tune, but i tried it a couple times on my 07lmm and never noticed any difference in mileage.
 

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I guess i'll just run with the 50 tune and see how she does, thanks for the help.
 

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I'll keep an eye on the egt's. Right now the highest ive ever seen is 1300 on the stock tune going up a grade pulling 18k.
 

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I get my best mileage turned all the way up. I've had the same results with my Cummins and Bullydog setup and my Powerstroke and Edge setup. The key is to not drive like a maniac though. With the cruise on and running 70 on the 135HP setting I can get almost 18MPG on the highway with 35" nitto's. I'm not worried about the high horsepower setting unless I dog on it. Then the tranny might have some issues....
just my $.02
 

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Running the 70hp profile and found this to be the best for mileage. Cruise set at 65 I can get 20+ on level ground but that changes (aka 'drops') up the first mountain range.
 
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