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diesel or gas

1828 Views 26 Replies 22 Participants Last post by  TxFire
Hi I just joined and my dad and I are thinking of purchasing either a 5.9L or 6.7L 2500 RAM. My Dad doesn't like the idea of $4.75/gal diesel, but I think the mileage will make up for most of it. We were thinking about getting a gasser, but I don't think that would do too well in the mountains with 11,000 lbs attached. Is 20mpg highway possible with the 3rd generation 5.9 or 6.7? Which gets better mileage? Thanks
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I can tell you that it is a fact that diesel is more expensive per gallon (duh!) but it is cheaper to run a diesel truck per mile over a gas truck. As for mileage, it seems that you will get better mileage from a 98-02 model truck.
I have a 6.7 megacab theres still alot of trial and error for this engine to see those mpgs I heard of other guys with the 5.9 that are seeing those kinds of mpgs its a matter of what you prefer really good luck
5.9 gets better mileage but the 6.7 is a stronger running stock engine! Gas towing in mountains suck trust me!
I believe the 5.9 gets better mileage because of the lack of most emissions parts found on the newer 6.7. But anyhoo, I would definately go diesel.. and this is NOT comming from a "diesel head" (yet!). Im looking for a CTD to replace my gasser as a DD.. figured Id save around 1500/year driving the diesel as opposed to the gasser. Hope I helped you a little, and Im sure some more guys with better answers can/will chime in!
mines a 99 4x4 and im geting 23mpg back and forth to work:thumbsup and the speed limit is 60mph. loaded iv never checked but for sure alot better then a gas and with power to play.:welcome:
First of all :welcome: I am honestly getting 20.6mpg hand figured on the highway at 70-75 mph. My brother in laws Ha Ha Hemi gets 15 mpg. :lol3:
i always had gassers .. and they were all dodges.......this is my first diesel.....and gettin 500 plus miles on 29 gal...........cant beat it!!!!!!!! i fill up once a week ....instead of twice......u do the math!!!!!!!
I have a 5.9 before the lift i was getting 18-21. when I had a gaser I would tow a 6,000lb boat and I would constantly have my foot in it. I think my avg. mpg was 9. go for the diesel if you tow
i should have said that my 23mpg was hand calculated i dont have one of those liy o meters:thumbsup
5.9 is the better engine for gas milage
From what you describe, I think you'd be happier with the diesel.
A lot of people have a diesel and don't need it, sounds like you do.
I know two cowboys that have 5.9's, they tow stock trailers, and goose necks with heavy equipment. Manual trans, exhaust brake, pretty good mileage, no DPF.
I also know a veterinarian with a 5.9, auto, always has a Lance camper on his, and pulls his boat as well. Not as good mileage. These are all duallys.
Nice trucks. I don't like the white guages, (where did that come from?), but hardly a reason not to buy one.
just figured milage at 21.4 this week. It changes from week to week depending on driving style. I have a heavy foot. I will try to stay around 70 BUT??? road rage gets the best of me sometimes. I can pull the boat and stay around 18mpg. The worst was 14 loaded heavy crossing the mountain. The Diesel is definatley cheaper to opperate. I figure it cost .22 per mile against .25 for the gas, that is empty. Dont want to even think about loaded cost:thud:
What years of the 3rd generation 5.9 would be okay? Any significant changes? What about auto/manual? I heard the autos are the weak point, and the manuals can take more of a beating.
Any diesel will get HORRIBLE gas milage. Try puting diesel in it and it should do great!!!! It's "Fuel" milage

The 5.9 is better beacause of the lack of emission crap. Take all that stuff off the 6.7 and it does well too!!
:welcome: The 5.9 is the way to go.
I've owned my 2004 4X4 quad cab 6-speed manual for three months now. I bought it from a private party about a 5.5 hour drive away. I carefully calculated the mileage on the trip home... it was just a shade over 21 MPG. That was driving the speed limit... 65 MPH on the interstate & 55 on the state highways. The mileage drops to about 16 MPG when towing a three-horse trailer with my daughters' two horses inside. I'm sure that's better than a gasser would do.
get about 20.2 on my 2005, with a diesel you will have the pulling power you need especially in the mountains with a 11k trailer. respect your stock tranny and it will last with stock fueling
my dad has a 2003 quad cab dually 5.9L with an edge EZ set at 75hp and a K&N intake and he is getting 24.8mpg on the highway, hand calculated
What years of the 3rd generation 5.9 would be okay? Any significant changes? What about auto/manual? I heard the autos are the weak point, and the manuals can take more of a beating.
03-04.5 will be your best bet as far as mileage goes. Mileage is a little better with a manual, but if your towing, I would recommend an auto. The 48RE is a good tranny, as long as you take care of it. A stock 48RE can handle about 70 hp over stock before you start having problems with it, mainly converter slippage. It is entirely up to you what you want. Good Luck
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