Yea, its not very aero dynamic. I just dont understand how a nissan titan with a big @$$ motor could get better gas mileage. Jeep has always failed at providing their jeeps with good gas mileage motors. Heck my 4.0L tacoma gets 18-19 in town.
It's driving habits, your mileage, and what kind of driving you're doing. At about 5k miles I was getting 17.6 with cruise set on 80mph, 2 adult males(my dad and I) and hunting gear for both. I also sat in bumper to bumper traffic for 2-3 hours and that was going from Long Island, NY upstate into the Catskills. Yes the tranny kicked down a few times too. But here on the island I get a little worse(now I have 10k miles) because of traffic and its like 95% highway....I hate when people play with the gas.
Around town, don't expect anywhere near 18. I'm lucky to get 13, I usually average 11.5-12ish. But I have a heavy foot...
Btw this is with a 2011, oh and the hunting trip was in November(KK was stock), and since Christmas I added a brush guard so my KK gained a little weight.
Short version, give it time, and think about how you drive(heavy foot or grandma status?), what kind of driving(pure highway, mostly highway, sit in traffic alot, stop and go city?) and the mileage on the truck. Give it some time to break in, then worry a little about gas mileage....oh yeah, don't forget, IT'S A JEEP, it will never get good mileage lol.
That is exactly correct. If you do a lot of city driving and then when on the highway you drive 80 MPH you will never get 18 MPG in the Liberty.
The best fuel economy comes on the highway between 2000 - 2500 RPM which means driving between 55 and 65 MPH. And accelerating slowly to get there.
I did a fuel economy test with my Nitro on the Autobahn a few years back. First I drove about 30 miles flat out at 115 MPH (Nitro is governed at 115) and I got 13 MPG. Next I reset the trip computer and set the cruise control at 2000 RPM which was 55 MPG. Result.....26 MPG!!! I am pretty sure the same results are possible in the Liberty.
I drive 20 miles to work everyday and most of it is on the Autobahn. I drive 55 MPH. Co-workers fly by me. I guess I fit in the grandma status but I am ok with that. The oil companies already get enough of my money.
But when short distances are involved, driving flat out or driving sensibly, you still arrive only about a minute or two behind. You saved gas and you are more relaxed when you get there.
When I have to drive longer distances like 100 miles I do kick it up to about 70 MPH.
Sensible driving = higher fuel economy.
I keep meticulous records and for the 5 years I have had my Nitro I have averaged 18.4 MPG.
Supposedly the "perfect" speed on the Liberty is 63mph. And GermanyBert is right. We get our best mpg around 2k rpm. In the KK that's about 65-70mph. I guess the Nitro's 5speed is just a bit different. I know at 75mph I'm running about 2200-2300rpm(I set my cruise at 75mph daily for a commute to school, 70miles round trip really hurts the wallet in a Jeep). 2500rpm is up around 85ish mph.
Others have written that the perfect speed is 72 or 73 mph. I had a couple hundred miles to kill on flat level nearly deserted highway and played around with cruise and my trip computer. My mileage absolutely peaked at 72 mph.