[maninthemaze]

I have been looking for a truck for a while. This will be my first diesel. I have primarily looking for the 03-04.5 model for fuel mileage reasons. Is there a major fuel mileage difference between the 04.5 and the 05 model? If there is, can it been fixed with something from the aftermarket (ie Exhaust,Intake or Box)? I am very specific in what I want and am just trying to broaden my search option.
I am wanting a QC SB 4x4 SLT 6sp with a manual transfer case.

Thanks for your help!

 

[GSW]

The 03 to early 04 models have lower rated hp/tq and generally get better fuel economy than the late 04 (aka 04.5) and newer models. I'm not aware of any way to "detune" the newer trucks for less power/more mileage.

For fuel economy, my early 04 truck consistently got 19-20mpg with a small dip to 18mpg on winter blend. My 05 is 15-16mpg. If I hadn't needed to trade for an auto, I would still have the early 04. Plenty of power (305/555) and great mileage.

 

[JDiepstra]

Going to the 04.5 and up will cost you some. They have the cat converter and a third injection event to heat things up and keep the exhaust cleaner. In general, yes, going to the more powerful 600 engine will cost you some. And no, there is no easy fix.

 

[maninthemaze]

Thanks for the replies. I guess I will keep looking for the 03-04.5 models.

 

[Bigfoot13]

Thanks for the replies. I guess I will keep looking for the 03-04.5 models.

I don't think you are understanding what people are saying. The 04.5 has the third injection event and the cat, so gets the same mileage as the 05's. That being said, I put an OD unit on mine, and I consistantly get 19 to 20 mpg (empty). I am very happy with the performance of this truck. Some people say that adding a tuner such as a Smarty, if you run it on the right setting, can get you better mileage too.

 

[maninthemaze]

I probably worded that wrong. Sorry. I will keep looking for the 03-04 305/555 model. I knew that the 04.5 had the 325/600 motor and the worse fuel mileage. I just didnt know why the fuel mileage suffered. This is the first time I've heard of the 3rd injection event. Thanks again

 

[Bigfoot13]

I probably worded that wrong. Sorry. I will keep looking for the 03-04 305/555 model. I knew that the 04.5 had the 325/600 motor and the worse fuel mileage. I just didnt know why the fuel mileage suffered. This is the first time I've heard of the 3rd injection event. Thanks again

The 305/555 motor was a 49 state motor. The California version was only 250 horsepower. The new-for-04.5 325/600 motor included a 4 inch exhaust, a bigger turbo, a cat, and was smog certified for sale in all 50 states. Since I am in California, that was the truck I wanted!

 

[jjm]

The best I've gotten out of my 04.5 lately is 17.5mpg on the highway running empty at 75mph, 2000rpm. My buddy has an early 04 he gets 20mpg regularly. Best fuel mileage on the 3rd gens is the 03 and 04 models, best of luck to ya.

 

[Mopar99360]

My wife gets 19 city/hwy in her auto and I get 21 city/hwy with my 6 spd. Both 05's 325/610.

 

[rufushusky]

In general the 03-04s will do better but if you keep your foot out of it a 04.5-07 will do fine too. I get about 18-19 mpg with a 48re auto and 373s.