To answer the original question;
Common Problems/Complaints applicable to 2004. 5 Dodge Cummins pickups;
1) - reduced mileage compared to earlier engines (305/555) Most people seem to agree 2-3 mpg worse. The cause is the new emmissions regulations and the programming required to meet these regulations. Some people are experiencing even worse mileage and I believe that the most likely cause is one or more bad injectors or unrealistic expectations. Injector problems are rare, but frequent enough to mention. The rest of the engine is typical Cummins - bulletproof. Check out the thread on the miracle injectors as this is the latest carrot for the poor mileage crowd.
- 2) Sporadic vibration and/or quality control issues with the AAM rear end. Again enough complaints to mention. Test drive at 70 mph plus should be performed prior to purchasing any 3rd gen truck to avoid the issue.
Minor issues;
- the frost plug issue - this shouldn't be much of a problem anymore. If you have enough miles on the truck, its a non issue. If its on a lot it should have been tested and if its been built after the bad plugs were used, there is no problem. I think this was a much smaller problem than some people made it out to be.
- headlights still too dim
- some people complain of the comfort of the front seats (enough to mention)
- A-pillar blind spot is still too big
- miscellaneous complaints of noises or vibrations. Various causes although I believe a large percentage of the noises are typical of this engine and just can now be heard because of the multiple injection events.
- thin paint. Chips and scratches easily. More noticable on darker colors. A function of new environmentally friendly paint processes, perhaps, but an annoyance nonetheless.
- complaints of diesel smells in cab, mostly whilst idling at a stop. turning the HVAC controls to recirc can offer some relief. Haven't had this problem, myself.
- wind noise from the door seals. Most common at high speeds, gusty or windy conditions, and especially if hauling a slide-in camper. Several potential solutions including, new door seals, hinge and striker adjustment, bending of the window frame and the addition of aftermarket gasket tape.
- There are still complaints of no full crew cab or no 4500 - 5500, and you can search for the latest rumors in both regards. I don't consider either to be a problem with the truck, just a smaller product line than some of the competition (for the moment, anyway)
Feel free to add to this list. Please don't assume that I'm unhappy with my truck, because that couldn't be further from the truth. My '03 has had only the pwr steering hose vibration issue and my '04. 5 has had no issues to date (other than worse mileage than my '03). Love my truck.
Dave