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Discussion Starter #1
Hey guys. Recently bought an 09 Chevy 2500. It's all pretty well stock w the exception of having the dpf deleted. I'm getting pretty terrible mileage. 14.6mpg empty on the freeway, and around 10.5 towing around 5k. It runs and drives well for how many miles are on it, just bad mileage. I guess my question is could the previous owner have done the delete without properly programming the ecm? There is no physical tuner in the truck, and it feels pretty sluggish. Any help would be great.
 

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To answer your question in short No not that I'm aware of. I'm willing to bet he prolly used an H&S tuner and just took the module to sell it separate if it was a trade-in. Personally i would just get new tunes for the truck so you know whats going on or reach out to the previous owner if that's feasible and see if he can give you any info. Regardless i would get new tunes so you have the ability to set the tune to whichever you see fit. My personal experience is I get the best MPG's out of the higher HP tunes & change the tune if towing heavily.
 

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Getting harder and harder to find tunes for the 07.5 & up. I'd recommend motor ops out of Canada. I have also recently heard some good things from a guy in Canada that has a shop called Optimal welding. Stay away from H&S.
 

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Hey guys. Recently bought an 09 Chevy 2500. It's all pretty well stock w the exception of having the dpf deleted. I'm getting pretty terrible mileage. 14.6mpg empty on the freeway, and around 10.5 towing around 5k. It runs and drives well for how many miles are on it, just bad mileage. I guess my question is could the previous owner have done the delete without properly programming the ecm? There is no physical tuner in the truck, and it feels pretty sluggish. Any help would be great.
There is no way i am aware of to delete the DPF without either lighting up the dash with codes, or tuning the truck. Those are the only two options i know of. If you do not tune it, you will end up in reduced speed mode so this is not very likely to be. Your truck is tuned.
 

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Check out what denarli6.6 suggested

I wish mine would get that terrible of mileage empty and towing.
12.6 empty city/little highway 9-10 towing, my truck weighs 8450 empty.
If your going by the instant DIC mileage, that's your first mistake.
It will not even be close to accurate until you have several hundred miles since the last reset, and you still need to hand calculate for mileage.
The DIC is for entertainment purposes only.

My guess is:
Sluggish could be dirty airfilter and fuel filter needs replaced, a few things to check out.
You can NOT delete any emissions crap without proper delete tuning programming.

Anyway to track down the previous owner, maybe thru who you bought it from to find out what tuning you have?

The tuning could very well be EFI, any handheld device any tuner could have been used to load the tune.
EFI is the easiest to install and you do NOT have to put the vehicle back to stock to use the tuner on another vehicle, like most if not all can tuners.

The big concerns for me running high hp for better mileage, is that couple tenths gain really worth issues that come with adding more hp than the drive train has to handle. 'uhNo

A couple of tenths was the only gains I had with bigger hp tunes.
 

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Discussion Starter #7
I always calculate mileage. My truck is pretty bare bones as far as accessories goes. Rubber floors, crank windows(in a crew cab, wtf?) No fuel dic . I have a new k&n air filter& fresh fuel filter. It's just a total turd in the power dept. It'll barely break traction. I'm guessing it's just tired and worn out.370k on it
 

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I always calculate mileage. My truck is pretty bare bones as far as accessories goes. Rubber floors, crank windows(in a crew cab, wtf?) No fuel dic . I have a new k&n air filter& fresh fuel filter. It's just a total turd in the power dept. It'll barely break traction. I'm guessing it's just tired and worn out.370k on it

It may just need a proper tune to wake it back up. Theres lots of trucks on here hitting those miles with power to spare. Odds are shes not clapped out unless the previous owner either failed to do reasonable maintenance, or just beat the hell out of the truck whenever he could.
 

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Discussion Starter #9
At the end of the day it is just a work truck. I don't really want to make any crazy power that'll hurt it, but a little more would be nice. I know an overhaul is in the near future. Hopefully I can get another year out of her before then
 

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You familiar w wagler performance? He's a pretty big name here in Indiana. Does a lot of tractor pulling. Anyways his shop is pretty close. I may just let the pro's handle it.
 

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Couple of key points here.

What speeds are you running at "highway speed"? Anything above 70 MPH in these trucks kills the MPG.

Your towing MPG is similar to mine. I get 10 MPG pulling a 15k 5vr at 65 MPH.

At 370k miles, have the injectors ever been replaced?
 

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Discussion Starter #12
Between 70 and 75mph. To my knowledge the injectors are factory. I know the truck was owned by a construction business (hence the no frills interior), but I believe it has changed hands quite a bit. I bought off fb market place. I'm running 20x12x33 currently. I know it takes a lot to push that truck. I'm prolly close to 10k with camper shell and tools. My oil never smells like fuel, and I have no blow by
 

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Having 20X12X33 expecting good mileage, that’s ain’t ever goin to happen even with the speedo recalibrated for the tires.
Have you recalibrated your speedo with those tires or at least verify with a GPS how far off it is.
 

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I have 2011 with complete delete, egr, dpf, catalytic. I also run the h&s tuner which works great. This tuner can be unplugged and taken completely out of the truck but the tune stays. I’ve run it on all 3 tunes, economy, towing and performance. I get the best mileage by far on the performance and runs great with noticeable power and response increase. So long story if it did have h&s it could’ve been pulled and tune left in truck. Sounds like left in tow tune. Those mileage numbers sound about what I was getting. Now 17.3 city and 23+ hwy
 

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Oversized tires kill the fuel mileage on these trucks. Either leave the little pizza cutters on there and lighten up on the pedal or upsize the tires, make it look cool, stomp on it and get used to 15mpg and under. I prefer the latter.
 

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1. Ditch the k&n filter and put in an acdelco filter ASAP, no need to dust the engine and turbo for a 0 hp gain.
2. 14 mpg is 100% normal and average for an lmm.

This guy claiming 23 highway 17 city is either bad at math, the dash calculations are off (distance wise) or his truck is the only one in the world (I meet a lot of people that have the only truck in the world to get that high mpg)

If it was an lml that might be low, but lmms especially didn’t get great mpg. 14 at 10k lbs is fantastic mpg.
 
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Discussion Starter #18
I don't mind to sacrifice mileage for power, but the power just doesn't seem to be there. This is my first diesel also. No I've not recalibrated for the tires. Speedo is only off by 3mph so overall diameter is pretty close to stock. Just pulled my enclosed 16ft trailer to Memphis and back, only got 8.5mpg on that run. I knew it had to be tuned for the dpf delete, but was curious if there was some kind of shade tree trick around that. Now knowing that isn't possible, I'm curious what is my best route to go for a tuner. I know the tuner goes off what the ecm already has stored. My concern is that if my ecm ever gets cleared/ re flashed, it won't recognize the ecm if this anonymous tune vanishes. I'm finding out you can't really get a tuner now that supports deletes due to epa regs?
 
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