Reason for sudden gas mileage change?

Okay, I have a 2014 V6 Tacoma Crew cab...living in the sunny south (Texas) I've been getting around 20 city and 22 Hwy in my rig...this past weekend, I went to Indianapolis...the very best mileage I got was 20 Hwy, and the worst was 18...is this because of the cold? or is something on my truck starting to fail? This is also my first Tacoma...

 

I do think MPG drops in the cold. I don’t remember all the factors but it made sense when I read it.

 

How fast were you going? 55+ MPH your MPG will begin suffer. 45 MPH seems to be the sweet spot if you ever get stuck behind a Prius.

 

High speed interstate driving will not net the same mpg...

Time for spark plugs.......? synthetic gear lubes will help some....

synthetic 5w30 motor oil ? my '14 with MT best mpg has been 21.4

others will chime in with other ideas.....study chart in link to know where

the RPM sweet spot is for economy


http://www.offroaders.com/tech/gear-ratio-chart.htm

 

I'm using stock 245/75/16 tires and wheels, bt driving hwy speeds 70-80 mph...around 2200rpms...mileage before has been with the same setup , good tires, NEW plugs synthetic motor oil...I just couldn't account for the drop in mileage all of a sudden...new plugs wouldn't cause that would they?

 

Weird thought...change in elevation above sea level??

 

https://www.fueleconomy.gov/feg/coldweather.shtml

Edit: The reason I am focusing on the cold is because it sounds like nothing else changed. I highly doubt there’s anything wrong with your truck when this would explain it.

 

Up north the gas blends change in the winter and summer (this is in New England) I don't know what they do in the mid west. This does affect mpg and yes my mpg drops in the winter.

 

Welcome to TW. There are no dumb questions, only dumb answers. Certainly cold is a factor among many others.

 

I too am in New England. Normally I get 20 to 21.5 during the summer this drops to 18 to 20 in the winter. I have a 2014 DC 4x4 Trd off road with 111000 miles on her. Maintenance per owners manual and regular oil. She still runs like a top. The drop in mileage is normal in the winter with winter fuel and longer warm ups.

 

Did you happen to notice this after a fill up (up north)?? As someone already mentioned....winter gas mixtures. Texas probably doesn’t have the same recipe as those up north. I live in southern PA and my 2007 tacoma used to get 2mph less in the winter overall on average. The sweet spot for best MPG’s was between 40-45mph (V6 Sport).

A little bit of ‘winter gas mixture’ and the fact that you’re going 70-80mph? Yea...I’d say that’s normal.

 

Colder air = denser air.

More air = more fuel.

 

I get around 16-18 combined during warmer months and 14-16 during colder months.

 

Winter fuel its not as efficient as summer fuel. I usualy see 4 to 5 mpg drop 8n the winter.

 

If you're back in Texas, check you mileage to see if it 'recovers' before spending money on stuff you might not need.

 

I live @ 6K'.........

only go up from here........

21.4 best so fur......

 

Yup dam winter fuels. They put additive in gas and diesel fuel for the cold weather.

 

Well...back in Texas and after 1 full tank, am getting 17! something is wrong...filled up last night and am going to put injector cleaner in this morning and giv it a run...we'll see...problem is; it is unseasonably cold here today...probably have to wait till it warms up to really check mileage.

 

Winter blend gas up North causes shitty gas mileage.

 

Possibly the winter blend gasoline? A lot of areas change the gasoline blend in winter to reduce pollution, which has a negative effect on mileage.