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The Good Son!
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Discussion Starter #1 (Edited)
I have been tracking my mileage from when I bought the truck. I wanted to see what modifications if any would affect mileage and by how much. I have MBRP exhaust, down pipe back with Quadzilla Stealth 2. So for all that are on the fence about deleting the DPF here are my results. I understand that city and combined city/highway is not an accurate way of determining mileage because of circumstances of the commute, but neither is strait highway driving unless the conditions never change which they always do. I do feel that with over 40,000 miles I have a good idea of what to expect for all driving conditions. I need to install the egr blocker plate, but haven’t had time.

City driving – pretty obvious

City/Highway – at least half the miles on the highway, if not they went under the City category.

Highway – pretty obvious

Towing/Mixed – Any towing that was not a full tank of towing.

Towing – A 36’ foot Camper with 4 slides weighting around 16,000#

I might try using all AMSoil next but, I doubt that their products improve mileage enough for ya’ll to act the way you do. You Amsoil guys are like a cult!

The Old Truck


The Mileage





The New Truck


Mileage




Comparing the 2008 LMM to the 2009 LMM
 

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Fuel Mileage tracking

I have a 2005 LLY crew 2WD...bought it with 8K miles about 6 month ago.......have tracked mileage to about 15.2 city and around town, towing 6K double axle [email protected] 12.4 and unloaded highway about `18.3. have changed oil ...with Rotella petrolium based..and built a history at 18500 total miles. Now that I have a based line ...considering the air intake mods from killer bee and going with Amsoil thru the drive train. maybe a big oil cooler and minor tune....but nothing radicle.......any thoughts or suggestions?
 

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Great informaiton! nice to see someone back up their MPG claims with hard evidence.
 

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Wow that is an impressive spreadsheet! And I thought I was anal about tracking fuel. lol
 

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$1.87 fuel on 1/07/08 :(
 

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Vendor
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Great looking truck and very detailed information. Not sure about us being a cult but I would like to help if I can. AMSOIL offers an outstanding product. Is the change going to be significant? Depending on all the variables, some have seen up to an 8% increase in fuel economy.

Personally, I have it in the entire power train, including their fuel additives. I have seen a 2-3 mpg increase, again though you have to factor all the variables in. I drive mostly city, tow a couple times a month.

If you don't get that at least you are putting some of the best oil on the market in your vehicle to protect it.

Let me know if I can provide you some information.

Take care,
 

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The Good Son!
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Discussion Starter #8
I’ll let you know if I decide to try it but, I’m pretty happy with Mobil 1 TD. I’m not sure it is worth changing all my fluids out especially if the results are the same as the exhaust/programmer. I need to get more miles with current mods to get a better baseline. I really need to run a tank of all highway miles because the only highway miles she gets is with the camper on her.

KB,
Better not be any scratches down here side!!!
 

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I've found, via my hauling, that a non-towing 3500 DRW running 200 straight highway miles with the cruise set at 71mph, will show an increase of several mpgs with a low profile (not much higher than the bed rails) skid of 2-3k lbs in the rear, compared to running the same route empty. Better mileage with a 1-ton increase in mass?

SeTex, I'd like to see if you show this true with yours when you find those highway miles for testing.
 

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The Good Son!
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Discussion Starter #10 (Edited)
Hook’em,

My highway mileage is a little deceptive in that most of the miles were driven with less than 10K on the truck. I had three tanks that were all highway since and mileage for those tree tanks were 14.6, 16.6 and 17.1. All three tanks were interstate driving empty. Unfortunately when the truck is on the interstate I’m usually pulling a trailer. I will be taking a trip this thanksgiving around 1400 miles round trip empty.

Are you telling me your mileage increases when hauling 2000# in the bed? If that is the case I might try bags of sand or a few railroad ties and see what happens. If it was to increase mileage, a custom flat bed would look good and be a little more functional for me.
 

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wow, DPF???

Looks like you got better fuel milages WITH the DPF... are you driving it the same, or are you putting your foot in it to hear the exhaust? IoIzzz
 

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The Good Son!
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Discussion Starter #12
I played the first tank or two but, drive very easy most of the time. I would like to try and get around 17-18 in town. The mileage has increased by about 0.5 mpg. Small gain for the price of the mods. My 2001 got around 17.5 mpg city and 19.5 hiway all stock. I would love to see those numbers again. City driving didn't affect the 01 near as much as it has the 08.
 

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I have not noticed any gain in mpgs. It used to be when all stock I was getting the same mpgs now I just have more power. I want to use the power so in real life my mpgs have gone down. Maybe I should of left it all stock. I don't know what these other people are doing to get 2-5 more mpgs. I drove 100 miles yesterday at 60 mph no increase mpgs. What level tunes are people running to get these kinds of gains?
 

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Well, you have opened my eyes to the DPF, I ordered the Banks Monster tailpipe... I liked the looks and it keeps the filter, No Black smoke. Thanks for all your logging.
 

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The Good Son!
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Discussion Starter #15
Well, you have opened my eyes to the DPF, I ordered the Banks Monster tailpipe... I liked the looks and it keeps the filter, No Black smoke. Thanks for all your logging.

I would have probably deleted the DPF at some point but, not at the expense of my warranty with little to no mileage change. I have read on here all kinds of numbers about how much fuel is used in regen and there is just no way. Based on my mileage I would guess it is a gallon or less for regens. 15.6 mpg times 30 gallons equals 468 miles now divide that by 31 gallons and you get 15.09 mpg. My truck used about a gallon per regen and that matches my mileage
difference. Numbers don't lie!!!
 

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The Good Son!
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Discussion Starter #16
Updated the first page with the new numbers.

I'm glad they got the site fixed. I have been eager to update. Check out the last entry 20.8 MPG!!! I had thought the exhaust and programmer hadn't helped but, now I think I may need to give them a little more time.
 

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good info! I keep going back and forth on the DPF. The MPG doesn't seem worth it. The smell and soot are nice and clean with it. BUT I am in this truck for the long haul, and the added heat of the DPF concerns me enough to consider its removal. I'd like to ditch the EGR and the DPF, for the overal health of my truck.
 

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The Good Son!
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Discussion Starter #18
The DPF and the EGR can Only hurt the overall health of the engine but, everybody wants smog free clean air.....what ya gonna do!:D
 

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wierdly, I've noticed better mpg with 4 other people in the truck compared to just me, making the same drive. while I didnt calculate it by hand, just by DIC, when it goes from 18 to 20 i do know it is an increase in mpg. This is crusing at about 80mph. 135 tune on Quad.

with the dpf stock tune, i was literally only getting 16.5mpg on the DIC going 80.
 
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