sounds like something is going on w/ your truck man, maybe a bad o2 sensor, maybe something simpler, did you change the air filter? what else has changed on the truck, give us a complete list

 

I fill every day simply because gas guage is not accurate, and prices can jump 6 cents over night here. THus I constantly check my trip mileage. THis is results from our 94 5.2 4x4 with auto. What I have learned over the years is highway mileage is predictable because we can control it. Running in your RPM range and keeping your speed up, say 65, and good driving habits increase mpg. Running slower eats and simulates city. Example, two nights ago interstate was bad and trip was fluctuating between 30 and 40mph. Mileage average for the day was about 14.9 highway. On days I can set cruise at 60-65 sit back enjoy the trip I average 16 to 18 depending on back ups etc, but 17.8 is a valid claim for most of the time. I dont feel bad about that because I live in the mountain up from town and thats a pull every night after filling up, Good part is I pick it back up in the morning running downhill. I also use my truck as a service truck and carry 2 to 3 hundred lb of tools and supplies all the time. City driving is non controable because simply idling in traffic waiting destroy's the mileage. My CAI just arrived today so I will keep an eye on the mileage with that installed and let you all know.Strange thing is I had a 2004 5.2 that had to go bye bye. It was paid for but some drunk decided to rearrange it and it was never the same after that. It got 20 to 22 on the highway, and 13-14 in town. It would get 16 interstate driving 65 traveling from Charleston W.V> to Morgantown W.V. but would get over 19 on same trip running 69 with tailgate down. That little lack of drag coupled with the higher speed kept it in O.D. thus the better mileage.

 

you did NOT have a midsize dodge w/ the 5.2 that was made for model year 2004, they stopped selling the 5.2 in the dakota durango platform in the year 2000 you probably had the 4.7 based on the mileage numbers, however the rest of what you say is accurate

 

Yeah what shrp said^

If you had a 2004 then it either had the wimpy v6, the 5.7 hemi or the 4.7. The 5.2 was only used 98-00.

 

the 5.7 was not offered in the dakota ever, in the durango in 04+(just to clarify)

 

Yeah in the Dakota case they only offered the V6 and the 4.7 in third gen.

 

Shrp: At the 100K interval, I...
Changed engine oil and filter (every 3000 miles)
Changed trans filters and fluid (with dealer parts and fluid)
(I have the 545rfe trans with 3.55s running P265/75R16)
New plugs (cheap champion copper cores cuz Hydra, my uncle, and the sticker under the hood say so!!)
Air filter (Wix paper filter)
TB cleaned (with new gasket)
MAF cleaned
IAC cleaned
New ceramic pads fr and r
Upper and lower BJs (still had originals)
New tires
4 wheel alignment
PCM reset

My uncle is a mopar master mechanic and has a DRB scan tool. I could have him scan my D but the check eng light is not on, so I don't think a code would pop up for any thing. Or should I just change the O2 sensors just because? The engine runs fine, it has no hesitation whatsoever when I want it to move. It does have a slight, almost not noticeable, roughness in the idle. I'm just kind of dumbfounded by the loss of mpgs I have now.

I checked my spd and rpms on the x-way tonight and it was 65 mph and about 1600-1700 rpms. I was off on my earlier post about this info.

 

****ty gas maybe?

 

I stand corrected, never paid attention to engine size in the 2004. The mileage delta make sense though. As said in other posts from you guys all the other mileage stuff applies to all vehicles. Update on MPG, Yesterdays driving was mostly town and roughly 25 miles rural driving on open two lane road. It averaged 15.5 so I conclude it is finally where it should be. I am going to install the CAI this morning and see if there is a delta. I do use 2-3 ounces of Lucas Fuel conditioner in every tank. The mileage numbers are post lucas. When I bought the truck it was getting 9 - 11 so I am thrilled. I just got the Granatelli CAI yesterday lets see if it lives up to its claims.

 

I always go to shell and fillup with 87. I probably should use the better gas but I don't due to budget. I never go to the cheapest place and get water! And I also use the Lucas fuel Conditioner about every other week too.