thenrie

First post guys. Getting ready to buy a used Dodge Ram 2500, 5.9, 6 sp man. Fuel mileage will be important to me, so here is my question: Which model year and options combination consistently give the best reliability and fuel mileage?

For example, my dad has a 2001, 5.9, 6sp manual, that consistently gets 21-22 mpg, no matter what kind of driving (he won't sell it to me). It only goes below that when he is towing...then it goes down to about what a regular pickup gets - 13-15mpg. I have been told to look closely at the 2004-6 gen 3s, because of the HO motor, but I don't know anything about the fuel mileage issue with those. I have also been told that later models suffer in the fuel mileage area because of new smog regulation. Please chime in and help me out.

Sorry if this appears to be beating a dead horse, but I have gone back a couple years on threads and haven't found answers to the specific questions above.

Gumby

When I had my 03, I consistently got 16/20 city/hwy mpg. My 92 gets 18/22.

LongRanger

My 2006 regular cab with an automatic has hit 23 mpg at 70mph with ac off and no headwind. The manual on the 2006 has a lower OD ratio, but I imagine that a 2006 manual with 285/70 tires would do about the same.

rip 112

The 03-04s are known for getting the best mileage. Fuel pump on them are weak links, but easily fixed. After that they hold up very well.

thenrie

Rip, does it seem to make a difference whether they have the manual or automatic trans? I actually prefer the manual (male alpha ape sounds here).

rip 112

Well from what I've seen no not substantially. The auto may get a tad better because of gearing but not enough to avoid a manual. I get 20mpg in almost all conditions besides towing heavy. Towing light I still see 19mpg round trip avg. I love having a manual, sounds better, more full control of your gears, less maintenance and more reliable.

And for the record, the 03-04s are considered the HO or 305/555 motors, the 04.5-07 5.9s are referred to as the 600 or 610 engine. 03 was the introduction of the HPCR (High Pressure Common Rail) motors.

lgp9999

I've never seen any data that says that the 305/555, or any 24v for that matter, get's better fuel economy than the 12v. I would say the difference is minimal, although I believe that the 12vs make slightly better numbers.

If economy is a primary concern, then the 6.7 is the one and only that I suggest you stay far far away from!

Midnite

I would agree that the 12 valves have a slight edge in mileage. You'd also want a regular cab, 2wd model for lower weight. Bump the injection timing up, free up the exhaust and intake, and you should have no problem hitting 22 - 24 mpg, maybe even better.

Mike

rip 112

Its just so hard to find a good 5 spd 12valve. Its a gem in a rough of rocks. Plenty of autos selling though.

Oh and my comment on the above 03-04s and mileage were assuming he was looking at 3rd gens since he specified 04-06.

I concur a good ol 12 valve will make better mileage. I've seen them break 25mpg alot.

roger.t

i prey for those kinda numbers. the best that i have ever seen mine was 16. so i would agree stay away from the 6.7. now i have seen a 6.7 hit 22 but that was after all of the emissions junk had been removed and a smarty installed.

thenrie

I'm not particularly sold on the 3rd gens. I was just told by a mechanic (my nephew) that, in his opinion, the 2004-6 were the peak years for the 5.9, so far (quieter, higher hp and torque, minimal smog stuff). After that the epa stuff started really having an effect.

What is set, though, is that I need a 3/4 ton 4X4, preferably a Quad Cab Long Bed, 6sp manual. I'm finding long beds hard to find, though, so a SB is not out of the question. While I like a manual best (durability, control,...macho), I have not totally counted out an auto.

My needs are these: First, a daily driver and work truck, hauling carpentry tools, lumber, and towing a loaded contractor's trailer around Pittsburgh; second, a long-distance hauler I can tow a horse trailer, utility trailer, or 5th wheel camper trailer with; third, durability. I plan to have this truck a long, long time.

Brand new is not an issue for me, since it will be old soon enough. I want durable. If the recommendation is to go with a 96 and I find one under 200K that is in great shape, I'll be happy with that. If the recommendation is for a 2005 and I can find one in my price range, I'll go with that. This is why I'm looking at a Dodge and not a Ford, even though I have been a Ford man all my life. I had a hard time finding the words durable and diesel in the same post on the Ford forum. When I did, the fuel mileage was poor.

What years were 12v and 24v? Is there anything I should be looking out for as I look at and test drive Dodge Ram trucks, good or bad?

lgp9999

12 valves were '89 - early '98 and will be as faithful as your dog. 24 valves were '98 (most of the model year) to present. The '98-'02 24v has a VP44 injection pump, and they're known to not be the most reliable over the long haul, and they will cost you a lump of change to replace.

Reading your desires, I recommend a '94-'98 12 valve. '96-'98 with a manual transmission will have the 215hp pump rather than the 180. Either one you get can be made much more powerful than the 3rd gen for minimal cash.

When test driving, make sure you look for oil leaks from the front of the engine, as that will often be caused by the KDP (killer dowel pin, much can be found in a search) falling out and cracking the timing case. When you find a good one, take care of the KDP immediately. It will cost you a nickel and a few hours of labor, but it can save you thousands!

With a 12 valve 5 speed, put on a 4" exhaust, 13" clutch, pyrometer and boost gauge, grind the fuel plate, and put in a 4k GSK. You now have a truck with more power than a 3rd gen that will tow anything you throw at it. A 5 speed's only weak link is the clutch, but if you got an auto, depending on how you grind your plate, you are most likely already throwing enough at it to grenade the stock transmission in a short time.

thenrie

Just wondering, would it be difficult to swap a 6sp manual into the 98?

RedRewster

My '01 QC LB 6 spd. 4x4 that I bought w/100k and sold w/ 260k got 23/25 at 65 on the highway and 18/19 around town. My mods included:
Edge Juice w/ attitude- always on setting 2:MILEAGE and fuel setting on lowest.
285/75/16 Cooper STT's
Straight pipe- just removed muff and cat, nothing special
AFE stg. 2 CAI
Silencer Ring in the GloveBox
and I had .352 Gears- Truck topped out at 122

My '07 QC SB 6 spd. 4x4 5.9L that I just got with 100k on it gets 18/19 on the highway at 65 and I have'nt had a good opportunity to get around town mileage yet. mods are as follows-
Straight pipe
K&N in stock air box
315/70/17 BFG TA/KO's
Has .373 gears- Tops out at 101
Smarty S06-PoD- corrected speedometer only. Have not played with tuning yet.

I'm just giving you straight facts on two of my Dodge Diesels I have information on that I trust. My trucks w/ automatics were tricked as much as I could afford. I 've heard some fuel mileage stories that I found to be pretty bogus from people that seemed credible. Hope this helps.

lgp9999

Very easy if you have a donor truck. Not too hard otherwise. Personally I'd stick with the NV4500 unless you will be pulling EXTREMELY heavy extremely often.