I got an 89 also, I average about 12. But I also drive like a grandpa. I drive mostly hilly rural roads between 45-55mph. Easy starts and stops. I've been driving it a little harder lately though. We'll see if that makes a difference in anything. If you have a power/comfort switch, make sure it works and put it on power. It drives much better.

 

was getting 16ish on 30's now I'm getting 10.6mpg on 33's

 

Extra jealous of you with the diesel XJ! When (if?) the 4.0 goes I'd really like to pop a 4BT or an Isuzu in there. Just love the rattle.

I've got some intake cleaning to do, MAP is probably soaked in crud, as well as O2 sensors still. BUT I've done caps/rotors/wires/plug/oil recently and ditched the cracked exhaust manifold. This winter I'm seeing about 13 MPG in town. In-city mileage I expect to be pretty low on account of warming it up to melt all the crap off of it in the morning and uhh drivethrough for my coffee on the way to work...

21-22 highway at an average of 1950 RPM in 5th gear with a full load of passengers lol (105-ish KM/H or 65 MPH for you red white and blue people down there). Stock 1999 5-speed on 225/75R15 at about 35 PSI. I think I've gotten better highway mileage without all those passengers on other trips, but I lost the fuel receipts

 

I get about 10-12 with my 87 xj 5in. lift 33's stock gears and about 298k.

 

it may get a little better as the engine breaks in a bit, something to maybe look forward to

 

I just took a trip up to Maine this weekend from mass. on the way up I set the cruise control to 70-75 got about 14 mpg. i was not easy on the gas pedal at stop lights.
I have a 92 auto with light rack, roof rack, a snowboard rack on top, heavy front winch bumper. 3" lift 31" Mt's. 3.55 gears, neon injectors, apn header, custom cat, 2.5 cat back, cowl intake

on the way back I still was heavy on the gas but this time kept the cruise at 60-65 and i got 16.8.

if i took all the crap off the roof I'm sure it would help but
I think gears are really the answer I'm looking for. seams like the jeep cant ever find its happy place between 3rd and 4th.

 

The first long trip I took (from Denver to Aspen by way of Winter Park, and back to Denver) I averaged 20.5 mpg which was impressive to me since that's a lot of up/down mountain driving. Since then I've installed a ski rack and combined city/hwy has been around 16/17.

 

2004 4WD with SelectTrac & Mobile 1 - Getting about 17 mpg overall (mostly rural and some highway), about 21.5 highway only, 15.5 pulling 18ft boat

 

All stock 1999 with new plugs, wires, cap, rotor, both O2 sensors, exhaust manifold and new pipe to the cat. The cat and back is OE. I get 11-13 MPG city. When we take long trips, it will go 300 miles without using a single drop of fuel... but the motorhome pulling the Jeep gets about 9-10 MPG.

 

Combination highway & city 18 to 19 daily driver cosistent. 98 5speed fully tuned & moderate driving habits.

 

I don't drive enough on the highway to know how much better my milage is, but around town, I get 14-15mpg. I have a 98 5 speed lifted with 31in tires.

 

My stock '96 classic gets 20mpg in mixed driving.

 

this is as bad as a diesel mileage thread. i get 10. 31's and stock 3.55's.

 

1989 with 4 inch lift, 4.88 gears and rolling on 32s, I get 17 MPH in North Dakota and 15 MPH in Wyoming LOL.

 

amen to that! if you are easy on those 4.0 i6 they get pretty good milage on the highway. the trip i got 21 mpg on was pulling over the pass of the cascade mountains . ithought that was pretty good for hill climbing plus the altitude has some effect on mpg. on the other hand i average about 10-11 mpg in town consistently which drives me nuts. how do i get 21 on highway and then 10 in town it makes no sense.....i baby it in town because lets face it gas is expensive.