2005 DODGE CUMMINS SLT
2500, QUADCAB, SHORT BOX, 4WD.
6000 miles

STRAIGHT PIPE INSTEAD OF MUFFLER
AEM BRUTE FORCE INTAKE
QUAD 65HP MODULE

I only get 15.4 mpg. I am not hard on the gas pedal at all, I drive it like a grandma.

I am going to unhook the quad and see if my miliage comes back.

When I first got it, I had 17.5mpg once, but don't remember if the quad was on or not.

 

You don't have gauges! Try driving with boost below 6 psi and exhaust temps below 600F. You would be very surprised how much better mileage you can get and even grandpa is a hotrodder!

 

What happens if you come to a hill? Do you just turn around to keep the EGT's and boost low?

 

I have been driving like a grandpa and the best I have got on a tank so far is 14.5 mpg. I have 2200 miles on my 06 now and would really like to see that mpg number jump.

 

If that's mostly city mileage then that's not bad at all. I see a little less than that in the city, but my truck doesn't always get warmed up to operating temps.

Strictly highway (and warmed up) I seem to get about 18. Hopefully that will improve a little with mileage and summer temps.

 

Whether or not the engine is warmed up makes a huge difference. I see a difference in mileage just by plugging the block heater in on cold nights.

 

Your mileage is bad because your truck is not broke in yet.STOP BABYING IT.....
Drive it like you stole it or pull a heavy trailer as often as possilble and it will break in faster..These engines were not made to just put put around with no load on them and will take forever to wear in if thats how you drive it. Run it hard and around 15000 itl get a lot better mpg. Rooster

 

I was told the exact same thing by a Cummins mechanic. These motors like to work. It's like a thoroughbred being used at a petting zoo.