x15 cummins performance mpg

You are 100% correct. I was so amazed how good this thing is. I wouldn't wish that POS pro star on my worst enemy.

 

My x15 has 605 horsepower with 1850 torque and it doesn't pull past 1800 rpm, it just stops. Is that normal??

 

It could be depending on the ecm program but why are you trying to pull higher then 1800?

 

I think Cummins and Paccar are bottom of the pack when it comes to fuel mileage and reliability. If you MUST run a Cummins and you want an auto, you may as well get their Eaton Endurant 12 speed with downspeeding. I’d also recommend the efficiency series. Unless you’re pulling true heavy haul stuff, the performance series is not necessary. The Endurant is an Eaton transmission but the brain is from the engine manufacturer, sort of like an open source platform. It will perform very closely to an iShift or DT12.

 

Or if you just like horsepower and fuel mileage can go to hell.

 

I guess. All that extra horsepower means more fuel and for what? A few minutes saved off your trip? I just don’t think it’s worth it. You know how I think though, from our back and forth in a different thread. I don’t care about speed or power, only fuel mileage.

 

Just makes driving more fun. Living life worrying about nothing but money and fuel mileage seems boring to me.

 

Then screw emissions engines. Get me a C16 built by mr. Haney!

 

Now that would be nice.

 

Wondering the best Rpm range for the X15?