Winter mileage, driving habits and tires.

WINTER MILEAGE:
Just curious if anyone else has worse mileage than me! Over the past few fill-ups I've only been averaging 14 MPG! During the summer months I recall seeing up to 21 on the highway and 17 around town. Is the winter blend that much harder on mileage?

DRIVING HABITS:
I have been letting my truck warm up for several minutes in the morning (-20 degrees) and often sit idle for several minutes throughout the day on the logging site. I off road my truck literally everyday through farm fields, logging roads and four wheeler trails. Rarely exceed 60mph and accelerate slowly.


TIRES:265/75/16 Duratracs, am I actually getting better or worse compared to stock? In other words seeing as my speedo is off, is my mileage calculation off too?

OTHER: Full tune up, plugs, wires, filters etc last fall.

This post is actually quite confusing... I guess what I'm wondering is:
Does my mileage seem correct for my driving habits and are others experiencing lower mileage in Winter?

 

More experienced members correct me if I'm wrong but when it's really cold out your cold start cycle kicks in and your engine will idle at a much higher RPM when you initially start it until it warms up to operating temperature. So that would be one reason why you use more fuel during winter.. Especially if it's as cold as -20

Hope that helps

 

Depending on where you are your federal government regulates a change in formula for the gas in winter. I'm in the Atlanta area and my gas mileage is always about 10% lower in the winter than the summer, no matter what I drive.

 

Winter blend, all that idling, plus on warm up they usually run richer to get things warmed up and such just like a choke on a carburetor. All these things add up to worse mileage in the winter.