Does winter milage drop down because of the winterized fuel or colder temperatures?

Also, when running the defroster, does the AC cycle on & off and also reduce milage?

 

Yes, I'm not sure, Yes

I usually lose 1 mpg as soon as they switch to winter fuel.
I don't think the cold weather would affect the mileage.
The A/C compressor will kick on and off while using the defrost mode. I'm sure it eats up a little fuel mileage..

 

Yes, cold weather effects mileage. The air is thicker (more resistance), differentials are stiffer, trannys are slugish, ect.

 

Another reason the a/c cycles with the defrost is to lube the seals in the winter. This allows for longevity for your a/c unit. It will (and should) cycle in the heater condition. Just a little FYI....

Jake

 

also with the colder air our engines become less efficient....colder air produces more power too a point, but at about 10 below celcius, the air is too cold and cools the cylinder, thus the injection of fuel is not as robust.

 

That's the part I was wondering about. Noticed when it really gets cold (0 deg. F) & running unloaded that the exhaust is a little white when running unloaded - as if it's pushing uinburned fuel out the pipe. It does this after fully warmed up. Would a winter front help winter economy?

 

I expected to loose a little mileage with the colder weather, but I dropped from 18-19 mpg to 15+ on the last couple tanks. Temps have been from lows near 0 to upper 20's for the past month or so. Does that drop sound excessive?

 

Alot depends on if you are buying blended fuel or running straight #2. I loose about 1 MPG running straight #2 between summer and winter.

On my 05 the air conditioner does not cycle unless I push the air conditioner button.

 

MPG drops in winter for several reasons. Blended fuel has fewer BTU's than straight #2. In my cold Wyoming climate, the cold differential and tranny gears create more initial resistance. As the engine reaches temperature and the friction warms the gear oil, the winter to summer differences are a less noticible.

 

??????

The defrost uses the a/c to pull moisture out of the air to make defrosting your windows more efficient, not to lube you seals. It does not come on in a heater mode other than the defrost.

 

i am down a good 2mpg with winter blend fuel

 

now that we are on winter fuel , and the fact im letting the truck idle out side in the am im down about 3-4mpg looks like ill only be pulling about 625miles out of this tank.... cant wait for it to warm back up and get back on #2 and see my normal 750+ mile tanks..

 

625 miles!! what is that? like 18 mpg out of winter blend fuel! i am getting around 13 mpg!

 

Last fillup, 22.57 mpg. (564.5 miles with 3/8 tank left or 564.5/25.01). Had to calculate it twice to make sure I wasnt seeing things. Also, the trip-time was about 13 hours and some change so that would average somewhere about 40 mph for the tank. And that is a higher mph than I normaly see. Usually about 35 mph. I think the cumulative mph for my truck so far is in the low 30's. Rush hour, gotta love. I'm not sure if they blend fuel this far south. Judging by my mileage, I doubt they do.

 

i did not notice that you were in houston- i doubt it too. i wish i got that mileage!