Now I'm new to cummins but not the diesel world (former 6.ut to )so this may sound a little but I recently purchased a 05 610, and with a 1000 miles on her I thought my fuel milage would be a little better. Now I know a millon different things account for better fuel millage but I just want to make sure my cummins is runnin fine. Running on the highway at about 70 empty Im only getting about 14.5-14.7 on winterizied diesel. I'm sure it will get better at around 10-15'000 miles on the engine but how much better ??

 

join the club. im getting the same mileage at 9200 miles

 

Congrats on the new truck. ( fill out your sig) Give it some time, couple k on it and it will creep up on you. You also need time to get used to it. Where the power is , ect.. You should see around 17-19 depending on how and where you drive. ( fill out your sig) Some get more, some get less. Pull your silencer ring from you turbo. ( wont effect warranty) You can judge you fuel consumption by listening to the whistle. The more it sings the thirstier it gets. ( fill out your sig) There are also tsb's out there for poor miliage but dont jump to soon, give it some time it should go up a few mpg. Also, fill out your sig

 

With more miles on the engine, it will begin to "loosen" up. When this happens you mileage will go up. My bro has an 04.5 and every 1-2000 miles his mileage has been going up. When New he saw 9-10, he's got 13k on it now, and he's gettin 16 with it. He also has the 4.10's in it. Have you guys got the update done?

 

I have found that low tire pressure was costing me some loss of MPG. I had cut it down to 40psi to improve the ride. Now, it's up to 70psi, rougher but MPG has gone back up. You will do better if you stay with smoother highway treads instead of off-road tires. Beyond that, it's all about driving conditions & driving habits.

 

New, tight engine hurts some, and so does winter fuel. Extra winter idling time does too. Wait for spring, go hook up a heavy trailer, and don't look back.

 

yep.You will eventually see 15 to 16 max at 70mph.Stay around 1700 rpm for best fuel mileage.these 05 610's are thirsty .

 

yes they are! i'm only getting around 14-15 MPG city and 18 hwy. my 03 would get around 20 MPG hwy. it was a 6 sp though.

britt

 

Due to emissions standards introduced the injection timing is retarded (literally)with the 610's, they will prolly never achieve the mileage of the 555 engines. It will only be worse with the G56 (steeper OD).

Unless the aftermarket people (hello TST, Ramifier, blah, blah) come out with a timing box for fuel economy.

 

7000 miles on mine and I average 17-19. I did have the control module flash done at about 3000 miles and that helped. The easier I drive it, the better the MPG's are. Love this truck!

 

*not that Im suggesting altering emmisions standards*

Will products like the Hypertech tuner allow you to adjust your timing? What about more brute force methods, like "tweaking" your crankshaft position sensor?

 

There was a thread about the sensor thing. It would be harder than its worth. Not sure about the hypertech tuner. I just don't have any experience with it.

 

I also have problems with fuel mileage. I had a 2003 4x4 dually with a 6 speed and it got almost 17mpg. However, I now drive a 2004 4x4 dually with an automatic and I get 12.6 mpg at the best. I've never been able to get better. If i'm towing a 20ft stock trailer empty, i'm lucky to get 10mpg. The mileage was the same when it was new and even after 24K miles, its still pretty bad. I read above that there is a TSB regarding mileage issues. Is there anywhere on this site that the TSB are listed? Any suggestions would be greatly appreciated.

 

I would say there is something wrong. I have gotten 12.5mpg holding it almost WOT with 4.10's and an automatic for 300 miles (85 mph ish).

The TSB is only for 325/610 motors (look at the data tag on the side of the valve cover for hp)

 

I'm finally seeing some mileage increases. Last 3 times I ran empty and highway trips @ 65-70 I got 20.2 in Florida, 19 and 19.3 here on winter fuel. In town, hopping here and there a few miles @ a time I got 13.5. I have 2004.5 6-speed/3.73 Quad cab, short bed. AFE 7 drop-in and Airaid MIT. Just turned 12k miles

Seems it's starting to loosen up.