detroit diesel 12.7 vs 14L

Discussion in 'Ask An Owner Operator' started by vader696, Jan 18, 2011.

  1. vader696

    vader696 Bobtail Member

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    ok first off like to say hello newbie to forum trucking since 93 with a break last few years and looking at getting another truck still have my own authority so thats the route im taking to get back on the road now to the question,the 12.7 it is 2003 is that a pre EGR engine and is there a big differance in the 14L that is in a 2004 or 05 that im looking at,have heard the pre EGRs get better fuel mileage then most of the engines that are equipped with an EGR and i understand that trans and rears and weight all make a differance just looking for basic feed back on the two engines from people that drive them my last truck was a new one back in the day 1998 12.7 500hp on a 10 with 370s if i remember correctly and it really did good on fuel avg was around 7mpg thank you for any info and i know i am crazy but would seem i miss driving a rig hope all stay safe out on the big road peace all
     
  2. MedicineMan

    MedicineMan Road Train Member

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    I average barely over 5 with my 14l set to 455hp in a columbia. I run heavy and fast but it really doesn't matter, if I run 65 i still wont see 6mpg.

    I'm currently looking for a classic or a 379 with a 12.7 detroit as i've gotten up to 7 in those trucks in the past

    and to really add insult to injury my buddy is driving a 95 shaker with a 12.7 set to 470. and even with the higher rated tourque setting on my 14 he still pulls as good or better then me and he's doing it at 7mpg
     
  3. vader696

    vader696 Bobtail Member

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    thanks Medicine Man did like my 12.7 know anything about these EGRs and when they started to use them thanks again vader
     
  4. josh.c

    josh.c Road Train Member

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    They started with EGR for the '03 engines, but there are plenty of '03 trucks with '02 engines.
     
  5. vader696

    vader696 Bobtail Member

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    ok so if i check engine stamp should give manufacturing date and if there is an egr its set up behind the turbo so i will be able to tell correct, thanks for input,Vader
     
  6. Dryver

    Dryver Road Train Member

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    A Columbia with a 14L should see better than 6mpg all day long. Something don't add up MM, what size right boot do you wear?
     
  7. country29

    country29 Medium Load Member

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    dang mm, already unhappy with your columbia, you aint had that truck long. truckpaper is full of classic's with 12.7's but most have higher mileage, but there are some gems scattered across the country, good luck to you.
     
  8. 25(2)+2

    25(2)+2 Trucker Forum STAFF Staff Member

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    12.7 with EGR was limited to 455 horsepower at the most, at least from what I know about,so if it is higher, it is most likely non EGR.

    Some of those 14s run good, I drove one that was ok, and others not so good, 2004 was probably the worst model year for them. I'm driving a 2008 now, rated at 455 and it is pretty decent after they checked it over for rough idle and surging, and loaded a new program to the ECM. Can't tell about mileage yet, and really can't compare it to what I used to pull anyway.
     
  9. JohnP3

    JohnP3 Road Train Member

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    There is one number on an engine that gives you a little more information about how the engine will preform fuel mileage wise that is the EPA tag. It gives you the number of MM3 of fuel it takes to make the maximum HP. On a Cat it is on the oil cooler, Detroit's, and Cummins on the valve cover. If memory serves a 1990 Detroit 12.7 430 HP was 198. newer Cats are in the high 3hundreds.
     
  10. MedicineMan

    MedicineMan Road Train Member

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    i have half a dozen friend with the same truck amd they are all sub 6mpg. mine is better then most actually.

    you did see where i said i run hot and heavy right? im always 78-80k and i run i80 where im usually at 72-76mph. plus im an idling fool.
    all in all im not unhappy, im looking for a second truck not to replace this one. in over 18mo ive put less then $4k into tjis truck with almost 700k mi. on it.

    plus for enough money you can get the egr turne off ;-)