Need help with MPG

So who needs to run at 75mph n get 5mpg. When u can run at 65 n get 6+
12000lbs in box u should be getting 7+

I am finding more o/o r slowing down too now.
The drop of in the winter is normal.

But what else have u done?
Tires? Seen as much as 1mpg difference changing tires.
Gap between trailer n 5th wheel?
Think when it first started to drop off did you change anything?

 

WOW! All I can say to this is "Never Mind".

Igorance is a disease a person chooses to have.

 

If it's CRE than it's DD60 right? You might have to drop a cog and run in a lower gear at a higher RPM so you aren't lugging the engine down. I've driven new Prostars that have gotten 8mpg out of the box on a tight engine.

Check your DPF.

 

Yea, I am getting 7.1 right now on mine. (company truck) I would do better if the governor was not on it. Would not drive much faster, but my foot also would not accidentally go to the floor as often, causing it to go full throttle whenever it is not topped out.

I would have the air to air pressure tested. Could be in the charge air cooler or anywhere in that system, a leak would cause a good loss.
Also, many of the new trucks with the DPF's are having issues of not burning off enough when it does it's regen. This can cause back pressure issues.
Winter fuel will cause some of this loss as well as wind and other factors that others mentioned.
Plus 1 really bad tank of fuel can cause issues for weeks.

 

before i have the gov in my truck now without gov i have a better mpg,before when i was a companie driver my boss have a good mpg on his freightliner comumbia after with the gov was 0,5 worster ,more speed less schifting is better mpg in the hills

 

Depending on what kind of engine your running and how sick of having a governed speed limit. Check out a bully dog, or go to Full Tilt or Pittsburgh Powers Website.