In the summer time when the weather is warm, 70 to 100 degrees I average about 18 mpg, this is on the highway using the cruise control most of the time.

In the winter when the weather drops to the low 30`s to low 50`s my gas mileage drops to the low 16 mpg range. Not driving any different and still using the cruise control most of the time.

I was out today and the weather was a bit warmer at 60 degrees, and my mileage went up to 16.9.

Why would my mileage be fluxuating so much as the weather temp changes ?. Is this normal ?.

 

Could be driving habits. Could be wind. Would be tire air pressure in colder months. Could be the winter blend of fuel they use.

I wish mine got 16 at ANY time