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Discussion Starter #1
Just a poll of what people have experienced mileage wise post EFI? Primarily LBZ's please. Driving very conservative on economy, the best I've got is 18.1. Yes, papered with GPS. Towed a 6x10 covered trailer with 300lb paylod driving 60-65 and got the most, 13. New fuel filter, clean air, full synthetic. Sorry to be so long! Any help would be appreciated.
 

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05 LLY 19.8 on mild tune
 

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02 lb7 - 23 with additive/21 without
 

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Just hit 20.04 mpg on my homemade tun on winterized diesel and snow tires and that is at 65mph average speed. The truck just purrs.
 

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LMM, 5" exhaust and a 100hp-ish tune of Jess's gets me close to 20mpg on the highway doing about 65. Usually about 17-18 on the interstate. Last trip towing was about 5000lbs of hay and trailer, and that was about 13. Stock intake, fresh fuel filter, 285/70/17's and about 200lbs of mud :mad: Mileage should get better once summer blend gets here:hyper
 

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Last family trip up to Big Bear and Sequoia National park. Averaged 19 mpg on an 800 mile trip and that includes a lot of climbing switchbacks in 4hi in the snow and a long stop and go commute through LA. Bet I could have been in the 21/22 range had it been straight highway driving. Have not had a load behind me yet so no figures there.
 

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23.5 on my LB7 back in the day, with a light foot and a good tune I made. Now I dont even think i go a mile on a gallon.
 

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12.7 city about 16 hwy on robs tow tune, I got better mileage with my ppe, i dont get it
 

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Discussion Starter #10
Big Black Dmax,
Loose the AFE intake. I picked up a minimum of 1 1/2 mpg by going back stock. Have heard rumor of the MAF sensor incorrectly located on the AFE?
 

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12 city 18 hwy still experimenting to see which tune gets the best mileage
 

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I would consider that but my truck came with the intake allready on it so i dont have the stocker, im just stumped because i averaged 15 city with my ppe on its 90 horse tune.
 

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18.5ish with my set up
 

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16/17 City, 20/22 Highway running IdahoRob's 110 hp "tow tune".

Last Memorial Day I got 20.1 mpg between Idaho Falls & Boise on I84. I had the cruise set at 80 mph and I was the slowest vehicle on the road and no, there was no tailwind. I could hardly believe it myself...

All mileage is hand calculated...
 

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Guys, try different settings.

Tow tune is built for heavy towing and not for the best mileage. Things like turbo brakes and more boost hurt mileage in the tow tunes.

Every truck is different and will react differently to tuning. Things like tire size, intakes, driving style help or hurt mileage.

The biggest problem I see when a customer calls and is having mileage problems is there is an aftermarket air intake on the truck. When they install the factory one, mileage pops up at least 1.5MPG.

Also winter fuel is a huge factor, if comparing winter fuel#'s against non-winter fuel#'s there will be a big difference.

Lastly if you are not seeing the results you feel you should after testing the different settings, drop me an email with results and findings. What works for 100's of trucks, may not be working for your set-up. I'll make some changes and we'll try again.
 

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I would consider that but my truck came with the intake allready on it so i dont have the stocker, im just stumped because i averaged 15 city with my ppe on its 90 horse tune.
If you were getting 15MPG city with 37" tires and stock gears, you should go back to the PPE. That is very impressive. I'll refund your money if you send me the EFI/ECM and I'll put your ECM back to stock so you can use the PPE.
 

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LMM, 5" exhaust and a 100hp-ish tune of Jess's gets me close to 20mpg on the highway doing about 65. Usually about 17-18 on the interstate. Last trip towing was about 5000lbs of hay and trailer, and that was about 13. Stock intake, fresh fuel filter, 285/70/17's and about 200lbs of mud :mad: Mileage should get better once summer blend gets here:hyper
I believe that, most of my tunes get that kind of mileage.
 

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LMM, 5" exhaust and a 100hp-ish tune of Jess's gets me close to 20mpg on the highway doing about 65. Usually about 17-18 on the interstate. Last trip towing was about 5000lbs of hay and trailer, and that was about 13. Stock intake, fresh fuel filter, 285/70/17's and about 200lbs of mud :mad: Mileage should get better once summer blend gets here:hyper
I can get about 21mpg hand calculated running 65 through some good hills with a little bit hotter of a tune from Jess. And about 15-16mpg in town driving. On winter fuel if it is straight highway at 65 it is about 18mpgs, and city sucks because of my extended idle times.
 

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Discussion Starter #19
This post was just for a research point for me, in no way does this reflect on Rob as he has been very accomodating. For some reason, this D-max (I've had 4-others 3 same motor) gets the lowest mileage. Still would not trade it for anything else! Thanks for all input.
 

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I like hearing feedback from customers, good or bad. This is how we all improve.

Please make sure to contact me if there are issues with tuning. With over 700 trucks tuned, there is bound to be some that don't work perfectly.

PLEASE let me know if there are tuning problems. Kind of like a restaruant manager not hearing about how terrible the food is, if I don't know, I can't fix it.

[email protected]

Thank you,
Rob
 
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