So I traded my 05 6 speed dually 3500 5.9 L crew cab long bed 248,000 which got 15mpg for a 06 Dodge 2500 4x4 6 spd tranny crewcab longbed with 248,000 miles on it now. Motor has less than 150,000 on it, no blow by, just a few oil leaks best I can tell. The mud tires that came on it were bigger than stock so I get about 3% distance change in travel distance compared to the speedometer. The mileage gauge up my the mirror I noticed is not really accurate. its says I should be getting anywhere from 16 mpg, up to 20 mpg, but my truck gets more like 12 mpg by hand calculations and mileage adjustment or 1.03% with a leaky fuel injector and best high way I have gotten with almost 15 mpg with the injector leak fixed. I drove 75 mph part of the way for a 3 hr trip and slowed down part of the way to 1,800 rpms on the 3 hrs drive home. I just feel like every diesel i have never gets the fuel mileage I expect it to get. I don't drive real fast. I keep the rpms below 2,000 rpms most of the time, except when I was in a hurry to angelo last weekend to get there so the rpms got up to 2,200. I have had the truck for about 15,000 miles, changed the fuel filter twice. have fresh oil and oil filter in it. Air filter is clean, I can't remember if I removed the air re stricter T after the air filter, I know i did on the older truck, but I would have to check on this one. I put a smarty junior on the truck, but couldn't find a tire size change option. I heard these truck get better mileage when you shift 1,600 when possible and don't let it get over 1,800 rpms. I have only pulled a camper twice with it that was really heavy. Lately the only thing I sometimes pull will be a 20 ft boat trailer or dirt bike trailer that doesn't weigh anything. with 4wd I don't expect it to get 20 mpg every time i get in the truck, so 19 mpg would be a nice change. I let it warm up for 20 minutes before taking it anywhere. and let it cool down a few minutes before turning it off. its take a long time to warm up. I have a pretty steady acceleration, not really racing anyone off the line. when unloaded i take off in 3rd gear if its an easy straight away. get rpms up to 1,000 and get off the clutch for a smooth take off. if i have turn or on a hill, I take of in second to get the rpms up and shift early to get into 3rd. Anything I should think about? I am a mechanical engineer so I could always be over thinking something. With the long Warms ups I think my Thermostat is stuck open. It seems to stay at 180 Temp when idling and driving around it wants to get up to 210 degrees before fan decides to engage. and when the fan comes on it runs for like 30 seconds and then turns off again. I think its time to replace the thermostat. All the injector nozzles are new with the 60hp + set by diesel performance. Batteries are brand new. I want to delete the air heater coil on the intake, but haven't done it yet. The truck has no problem taking off. Drives like it has attitude The clutch and turbo are brand new from what I understand. i installed a smarty Jr, and it ran about the same though, even in ECO mode, i thought this might help the truck the most, maybe I need to redo the install since the injector leak is gone that made the truck a pain to start. I am open to ideas or questions if you think i left anything out. I am not a diesel mechanic, but I have become ok with 2 stroke motors. with diesels my work is somewhat limited.

 

Moving this to the diesel section.