Hi all... Well, after 3 PSDs I finally got a new Dodge/ Cummins... Truck is a H.O. Cummins with the automatic, 4:10 rear end, longbed quad cab... I bought this to tow a 36 foot 5th wheel with 4 slides.. Weight of RV is 13100 lbs!!!. Just got my first mpg reading... 14.1!!!! God this stinks!!! Will fuel economy get better???... Will the 4:10s hurt the economy that much?? How'bout the new automatic.... Is it good?? Thanks all... Dan

Is that loaded or empty? If empty that is about right for a brand new truck. These trucks can take up tp 20,000 miles to break in properly and start getting the good fuel #'s. If that is your loaded number's you should be dancing in the streets.

I'm sitting here with the same question, was a bit surprised on my first tank results, took a 500 mile trip starting with only 42 miles on the truck and first tankg only returned 13 mpg, not the .410 rears but the ho motor. wish they really offered an overdrive that spun the motor below 2k at 70 75 mph. I hear that is the point where the motor is most efficient but I'll be dammed if I drive that slow!

No, this is empty.. mostly hiway driving...

This is my second CDT.... Ive also owned 2 PSD's....My 02 CDT will get 20 mpg on a regular basis driving 75, ofcourse thats with a 3.55 rear end....However it only got about 15mpg before the 15,000 mile mark.....Im getting about the same as you with a 04.5 Quad cab 4x4 dually 6spd, which im not impressed with either...But am hoping i will see the 5mpg increase at the 15,000 mile mark....My dealer told me 10,000 but i guess well have to see..........

The key is to work the engine HARD! The harder you work the engine the better it will break in and the faster, thus resulting in better MPG. Tow your trailer even if you aren't going on vacation. The 04.5 does not produce as good MPG. 10k-20k is right for engine break in.

I'm doing 13-14 around town and 19 on the highway... consistantly. 35" tires and the high stance doesn't help it. It's very sensitive, mpg wise, to situations where my Dmax was more consistantly above 15 mpg.

hey hoot.....do you have pic of your gutted intake tube and the removal of the turbo silencer?????

just click on his link to the dodge image archive in his sig, good pics but as he told me ya gotta do some bangin to get that junk outa that pipe. prying twisting and cutting to get the plastiweld apart so you can remove the inards. then trim the outside flush and clean to replace the tube inside the flex fittings. gets kinda nerve wracking in the end as the piece of tubing is so thin walled once you remove the other parts.

The 600 doesn't do as good as the 555.Thank you EPA for the Cat. I have 4.10 gears and I get 17 in the city and 22 on the highway. Stock tires. I have heard the the 600 will get better around the 10000 mile mark. the more you work the engine towing heavy trailers the faster the fuel economy we improve. Good luck!

They took a major hit getting it 04 compliant. Ive spoken with several that got over 20mpg. In fact I havent met one with a bad one yet. Met a guy today gets 17 with a camper in it. He was complaining. Some people dont know how good they have it.