Machoo

So I've been tracking my mileage on my 2010 manual 2 door Sahara and it is no where near what others are stating they are getting and it seems to be getting worse!

It has hovered around 13 to 14 miles per gallon for the last several months. I am in California. I do spend some time in traffic but I work 5 miles from home. So my time stuck in traffic is really limited to about 15 min a day. My last fill up today dipped into the 12 mpg range. It's slowly been getting worse by little increments the last three months. I have almost 40,000 miles. Not burning oil.

Anything I can do? Anything I can check? Anything I should look for??

I typically shift in the 2500 rpm range and never rev it over 3000 so I'm not on the gas around town. I just think I should be getting much better

I do have the Garvin full roof rack on. I know that adds weight. But I've had it on for 6 months and it didn't really affect mileage all that much. I was only getting about 14 before. Or maybe the once in awhile 15. Before the rack I would only get maybe 17 on road trips.

Any help would be greatly appreciated!!!

ronjenx

A 5 mile commute, with 15 minutes of it stuck in traffic, (that's pretty much the whole commute?), will drag your mpg's down a lot.

The only way to tell what your JK is capable of getting is to burn a few tankfuls on the highway, or at least on roads with non-stop travel of about 35 mph, or more.

Jeepstin12

Over the last few months? Does CA have winter blend?

richlortz

Yes California has a winter and summer blend. The Bay Area has started to transfer to summer blend as of the beginning of March.

Machoo

Well like I said even on the open freeway I might only get 15 or 16. Even before the rack I would only get 17 on the open freeway

I know my ignorance is going to show here but I actually had no idea about the summer/winter blend deal and don't really understand how that works.

jk_sea

Some quick reading on summer/winter blend:
Summer-Blend vs Winter-Blend Gasoline: What?s the Difference?

The energy content of summer gas is slightly higher because the fuel is more pure, which = better MPG all things the same. Winter gas contains more of the stuff that burns off at higher temperatures and has lower energy content, so fuel mileage is decreased, all things being the same.

I know that "open" California freeways can run anywhere from say 55mph all the way to 90mph, so if you're pushing the Jeep beyond 65 or so, you're really eating fuel, especially with that roof rack. More air resistance, bigger tires, more speed = more fuel used. I owned a 3.8 at one point, with the 6-speed and 3.21 rear and Rubicon-sized tires, and 18-19 would be a good day up here in the Northwest on open freeways going between 60-65. Much beyond that, and it would really suck fuel.

Winds are a huge thing too. If you're fighting wind on the highway, that can really suck fuel too.

Things you can do/check: Make sure you're "up" on routine maintenance, make sure your tire pressure is correct, and even on all 4 tires. Check the brakes for any dragging issues.

Also, if you've ripped off the plastic air dam on the front--that will suck fuel too. It channels air underneath the vehicle more efficiently.

Jeepstin12

don't sweat what you don't know. That's why this forum is here. To learn and share.

Desert Fox

If you wanted a high mileage commuter car, selecting a JK, any model, was a poor choice. Next, your commute of 5 miles doesn't give the engine long enough to warm up and standing in traffic is still burning fuel - but you are not going anywhere. I'm actually surprised you are getting a good mileage as you are. There are a few simple things you can check to up you MPG by about 10%. Keep your tires at the correct pressure and maybe a pound or two higher than required. Check your air filter and make sure it is clean. When in doubt - change it. Use brand name oil and the correct weight. Change the oil and filter every 3,000 miles. Also use brand name gas like Shell, Chevron, etc, that have engine cleaners in their gas. You might even try a can or two of injector cleaner in you next fill-up. AND, if you are using your A/C during your 5 mile commute - that's not helping. As stated above, you should consider making a run to San Diego, down the 5. Set the cruise control at 60 or 65 Go as far as Chula Vista then come back. Your JK should easily get 20 + MPG on this run. My 2008 JKUX usually got 21 MPG on the highway and about 13 MPG in city driving. That's about what your city driving MPG is, not that far off. What you need to do is set your highway mileage "benchmark" to see if you are getting around 20 MPG. Good luck.

7kings

I have a 2014 JKU auto and don't ever break over 16mpg, even on highway runs. Let's face it - it's basically a refrigerator box on wheels. It's like driving a parachute.

nosnhoj1

'14 JKU with no mods here getting around 17 mpg combined and I'm thrilled. Beats the 12 mpg my '12 2 door got but that was with 35s and 3.21 gears.