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I'm in the process of getting a new vehicle. And I am Thinking of getting a truck. I have always wanted a cummins, so as of right now that's the way I am leaning. The one I am looking at is a 2007(first half) with 53,xxx miles. I don't really do any heavy hauling, just always wanted one. Some of my friends have gas trucks and they seem to think that I am going to get horrible MPG with a cummins, but the ones(24V) my parents had in the early 2000's averaged 25, so I know that's not exactly true. And their gas trucks are averaging around 15-17. I was just wondering if anyone had any input...I would really like to get one..just don't know if it's worth it or not. Any input would be greatly appreciated! Thanks!!!
 

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Decoder Ring Specialist
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Well for mileage its often the wrong reason to buy any truck. I average about 14 normally on a stock truck. I have been towing the 5th wheel around a lot (just got back from a trip too) and so that "hurts" my overall mileage, you can see my logs in my fuelly sig below. I haven't filled up for the last time since coming back from our trip yet, and there was at least one not quite filled tank which resulted in a better than actual and poorer than actual set of numbers but that tends to come out in the wash on the long run. Keep in mind I am abt 23k to 25k when loaded with the rv, so mountains around here, plus wind, affect the pulling average a lot. 7.5 is about the worst actual, with 9.5 being about the best, all hand calc not from the overhead ... on stock tunes though the overhead is usually very very close to reality for me.

The 14 is combined avg....if we take best/worst I see around 12-13 in town and 16-18 highway/freeway. Mountains affect that unloaded number a lot. 55-60 avg going on a camping trip without the big heavy 5th wheel I hit 18.5 but in the end I think 16 for the whole tank.
 

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I'm in the process of getting a new vehicle. And I am Thinking of getting a truck. I have always wanted a cummins, so as of right now that's the way I am leaning. The one I am looking at is a 2007(first half) with 53,xxx miles. I don't really do any heavy hauling, just always wanted one. Some of my friends have gas trucks and they seem to think that I am going to get horrible MPG with a cummins, but the ones(24V) my parents had in the early 2000's averaged 25, so I know that's not exactly true. And their gas trucks are averaging around 15-17. I was just wondering if anyone had any input...I would really like to get one..just don't know if it's worth it or not. Any input would be greatly appreciated! Thanks!!!
You definitely wont reach 25 in a common rail. ZOP is also in a 6.7 and undeleted, which doesn't help fuel mileage. (Not a hit ZOP just letting him know)

Once you go diesel you'll never go back!
 

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Decoder Ring Specialist
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You definitely wont reach 25 in a common rail. ZOP is also in a 6.7 and undeleted, which doesn't help fuel mileage. (Not a hit ZOP just letting him know)

Once you go diesel you'll never go back!
Oh, trust me, I know, I was just making sure to be realistic with him (and everyone else) with a stock truck. They don't get stellar mileage stock, and it DOES improve some if you can and are willing to remove the DPF (and EGR) but it's not likely to dig deep into the 20's for most people. Heck on the trip back in, the difference in 65-70 was about 0.7MPG from the EVIC....while the EVIC isn't absolutely accurate, it's within 0.2 every time for me so far, so 0.5-0.9 MPG difference for 5MPH pulling a 13' tall sail.

I know gas trucks wouldn't get the mileage I did on the trip, and sure as heck wouldn't have been able to pull like the Cummins. Despite pulling nearly full throttle in 6th, and dropping to 5th for hills through the worst of Wyoming, and much of South Dakota on the way out I *STILL* got 7.5. Running ~65, but with enough leftover to pull the whole thing to 75 if I needed to get around something. And I was passing damn near everything pulling but unloaded Semi's and Semi's running tuned up engines (talked to one guy who has a 575 Cummins ISX, turned up to ~750HP -- 2200+TQ ... he was the only one who practically pulled paint off the truck he went past me so fast, he was unloaded, but, that wouldnt' have made any difference with as hot as that truck was)

Truck never overheated, not even close, even with the 100+ temps we were seeing through the majority of the drive. Highest coolant temp I hit was 226 just before the fan kicked on. It went down to and held 219 for the rest of the grade (a couple miles or so of 6% or a bit steeper) -- that was when I was down in 45-65MPH in 4th (tops out at [email protected]~3000RPM w/ 3.73 gears) or 3rd, and the only things passing me there were unloaded pickups and cars. Anything with a load was overheating and/or running 25-35 at best on those two or three nasty stretches.

EGT's stayed in check, with a few sustained periods of 1300 being the highest she made. And by sustained I mean *MINUTES* -- and this was in 4th or 5th up over 2500RPMs. If Cummins felt 1300 was too hot they could easily make changes to back it down from that (the H&S MM Mild w/o Turbo set at timing 2 lowers the EGTs somewhat for the same pulls, cost of being slightly noisier, almost impossible to tell noisier)

This is 100% stock tuning (MM uninstalled, and Chrysler/Dodge/Cummins flashes re-installed using their tools) -- with the MM Mild W/o Turbo set on Mild she pulls better, and still doesn't overheat.
 
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