Observation on gas mileage
This is not a typical gas mileage post, I am not complaining or asking questions as to why my mileage is poor. I know I drive a jeep.
Ok, on with the thread.
My Xj gets 17-21mpg all summer depending on my driving conditions. This is good enough for me. When winter hits I see 12-15mpg almost instantly and 9-11mpg when I use four wheel drive a lot. My driving is the same year round. Obviously 12-15mpg is pretty bad for an XJ that has 235's and isn't lifted.
Now I understand fuel economy will suffer in winter. The air is more dense, it takes a little longer for the engine to reach operating temp, the oil takes longer to warm up, some let their cars "warm-up" before driving, four wheel drive, and there is a supposed winter blend of gasoline.
So factor all of that in and you'd expect to see some decrease in gas mileage, no problem. Kind of sucks, but there isn't much you can do.
However, this year in southern MI, we've had an unusual winter. It has been in the 40's for the majority of the winter, we've had very little snow, and more recently it's been in the 50's and 60's.
So almost all of the reasons normally given for poor mileage during winter haven't applied to this winter, yet my mileage is still 12-15mpg. The winter blend is the only thing left that I could even think of to explain my horrible mileage.
Two days ago I made a 120 mile round trip to the Casino. I went 65mph and 55mph the whole way. It should've been an easy 19mpg at the very least as it was in the high 50's all day and the driving was perfect. I got 16mpg. This type of driving is when my XJ see's its best mileage.
As soon as I got back, I topped my tank off again. I noticed the station had just been re-filled as the tanker was just pulling away. I topped the tank off and have been driving my normal routine(55mph, 45mph and half of the driving was 35 or less) for the past two days. I filled it up today and found that I got 17mpg. It was in the 50's again and the weather was perfect while driving. This is when my Xj see's its average/low mileage.
This gives me reason to beleive that the winter blend of gaslone should be given much credit in the loss of our fuel economey. I think the station just received the summer blend of gasoline as winter is almost over here and that is why I got better mileage. Now I need to read about why some vehicles see this loss in gas mileage, and if there is a way to help.
Hopefully some of you that DD your XJ's find this interesting, when 1/4 of your pay goes into the tank, I can't help but try to find answers.