rob_engineer

Here is the chart of my MPG data. So many times we see on here cmms t's such as I did this or that and my MPG went up. Well, this data shows it is impossible to make a conclusion about that by the seat of your pants. Only rigorous data collection will be a or to show trends over time. What I am seeing now in this data is a correlation to temperature. My MPG went up as summer approached and went down as winter came. I'll plot the data by month later. This chart starts last February and ends this past December.

rob_engineer

Here is the chart Mileage vs MPG.

rob_engineer

Forgot to mention- anything below 15mpg meant I was towing. Anything around 20 or higher was 100% highway during a long trip.

IRubicon

funny how you mention it going down coming into winter, b/c mine just did that coming into this winter. I bought it in July so this is my first winter, I don't have any long term test results

chris@offroadevolution

Do they change the fuel mixture in NJ? they change it out here for a winter mix.

jk_sea

The drop in winter MPG is usually due to several factors -- the primary one being the change to winter fuel blends for almost all pump-gas stations.

But, during the winter months, people tend to warm up their cars by idling, the engine burns more fuel when it's cold, and also if you're in a snow state, snow and/or the use of 4wd can really tank your mpg.

SCHLEPPN02

rob_engineer, how are you calculating mpg? trip computer / full tank?

rob_engineer

I have the data in excel both ways - jeep computer and excel calculated by # of gallons used vs miles driven. The chart shows the calculated mpg, not the jeep numbers.

jadmt

so it looks like your over all average is ~17mpg give or take over 20,000 miles.

rob_engineer

The calculated average is 16.5 mpg. Here is a chart showing how the jeeps computer compares with hand calculation. There are some outliers but generally speaking the jeep shows a little higher mpg compared to hand calculation.