I have an 04 dually 4x4 w/the 600 in it geared 410. I only have 2300 miles on it ,but im only getting 13mpg @ 70mph & 15-17 @ 60. Is this pretty normal & will it get better as its broken in? Thanks.

 

Yes,and yes.

 

Don't bet on it.

My '03 otherwise like yours gets 13 mpg on the highway (60-75) and 9-10 around town, at 16,500 miles. That's it.

My trip computer is almost dead-on too and I have yet to get it to even show more than higher 13's.

Rob

 

A Cummins can take considerably longer than 16,500 to break in.Have you towed HEAVY with it yet? Slow down.A steady 1,500-1,600 rpm with tires at 55-60 psi should get you more than 13. If not,i would wager you may have a fuel filter issue,maybe air filter too.

 

Yes! Towing about 9,000 lb with this truck helped it a lot. After about 1,000 miles of towing this load, fuel economy improved about 2mpg all around, hand calculated. Towing things with these truck is such a eye-opening, fun experience too!

 

My load carrying has been pretty good... I frequently carry a 4500# Lance camper and tow a 4500-5000# enclosed trailer... most of its first 10k miles were done this way.

1500-1600 RPM will be about 50 mph with my 4.10 gears.

Why is it that a friend in Texas with the exact same truck as mine but with 3.73s has gotten consistently 16-17 overall (unloaded) and 14 with his heavier Alpenlite camper, with even fewer miles? Same year truck too.

I'm already researching the best way to be rid of this POS. The local dealer won't help, the next closest dealer is 50+ miles away and it's not even close to convenient to try to get serviced there, assuming for the moment they'd even be sympathetic (I doubt it).

Time to just be rid of it.

Rob

PS: Already changed the fuel filter twice.

 

RobG,

When you sell it be certain not to buy another Dodge if you want better economy. My 04.5, 6 speed 3.73 with 14k miles and a 27' fifth wheel is doing about 7 MPG.

I made a mistake when I bought a Dodge.

 

I did not tow until I had about 10k miles....but towing 10,000# for a total of 1200 miles has not helped my mileage one bit....12 in town and 14 on the highway.

 

You fellas with the 325/600's i seem to recall a box/software that turns off the third injection event,maybe that would be an area to research.Dont get me wrong im not setting the world on fire with my CA.S.0 but i can see 18 mpg or so with a light foot on the highway.Mark.

 

I have a 2003 California 2500 and still not getting over 15 mpg on the highway. I have about 17k and I was getting about 17-18 mpg at around 10k miles.

I have changed the air, fuel, and oil recently and not one change. I took it into the dealer and he checked for codes. Nothing came up. One thing that is odd is he had the engine turned off. Not sure if that makes a diff or not.

Any suggestions would be much appreciated. I have two friends with 03 trucks and they are getting as high as 19-20 mpg with the same mileage? Something not right!

 

I get about 13mpg around town and 18-24 on the highway empty. When towing I get about 11-13. OK, I know I'm running one of those 235 Cali engines but from what I've seen posted here the rest of you guys need to take a serious look at your trucks. The only real difference is that I put AMSOIL in mine from about 2 months after I bought it. THen I towed accross country just to help break it in real good.

 

I have the 326/600 with 3.73s and went to 315 BFGs (much taller tire). I live in the west if I drove 55-65 I would cause an wreck by backing up everybody. With the 3.73s and tall tires my 75-80 mph RPM went down to about 2150. With only 2000 miles I am now up to 17 on hiway/city combo driving. 4.10s are in my opinion for guys that tow very heavy ar those with gas engines that need the extra rpm to get in the torque of a gas engine. I only tow 8k to 10k and (and need to do so at hiway speeds) and have no problems with the tall tire/3.73 set-up.

Try taller tires (315s fit without a lift) and or a gearvenders overdrive. That is if you otherwise want to keep the truck.

 

I have heard that a "reflash" may be in the works.. I have 2800 miles on mine and 'babying" the thing I can get 15 mpg..I would GLADLY reduce my horsepower to 300 and torque to 550 if I could hit 18 mpg..The thing is not broken in yet and this week we will be pulling a 5ver weighing over 13k lbs..Hopefully this will help bring the mpg up...

 

gdh11,

True statement! to expect 20+ MPG from a big heavy truck that can tow so much is asking a bunch. Some folks may be getting that kind of MPG, but the way I drive and the speeds I go, I am very happy. My past gas bigblock trucks (also crew cabs) got 10-11 hiway and 6-6.5 towing the same trailer and could not hold the speed on hills. Now I set the cruse in 6th and smile all the way!