Topic: Gas Mileage Thread

[chuck172]

chuck, sounds like you did it the right way, if that is indeed the correct mpg you get the Wrangler platinum award for saving fuel. I'd be interested to see the next tank where you're at (as in from the last fillup since you calculated the mpg).

I'm looking forward to the next fill too. Chances are the first calculation is high, I'd be happy with 18mpg.

[Jeffy]

I'm looking forward to the next fill too. Chances are the first calculation is high, I'd be happy with 18mpg.

You'll want to keep tracking it for a long time.  I'm averaging 15.56 but that's averaged over 3 years and all the mods I've done over those years.

[sharpxmen]

same here, average works better - i keep adding the quantity and do the odo difference since started and it's funny how my Jeep goes from even 12.75 to 17 mpg, it's actually all related to the long neck and lack of proper vents on the gastank, seen errors of 1/2 of gallon if not more based on which way the Jeep is pointing at the same gas station but averaging over several fillups makes it more accurate.

[Jeffy]

same here, average works better - i keep adding the quantity and do the odo difference since started and it's funny how my Jeep goes from even 12.75 to 17 mpg, it's actually all related to the long neck and lack of proper vents on the gastank, seen errors of 1/2 of gallon if not more based on which way the Jeep is pointing at the same gas station but averaging over several fillups makes it more accurate.

Since I did the tires, I've brought up my average from 15 mpg.  I get a pretty solid 15.5-16.8 mpg City.

[aka-justin]

The I6 in my Rubi has been getting 13-14 mpg to work on average - 23 miles mixed driving each way. If I drive it like a tractor at 45 mph, I'm getting 14.5 consistantly. Longer distances, I've seen as good as 18-19 highway, but usually involves hills and average is more around 16. Banks cat-back exhaust, AEM dry intake, ECU Programmed Hyper-Tech Stage 3, 5.13 gears, 4" lift sitting on 35"s, and keeping at or below 55 mph. Torque Android app has also helped me monitor my gallons per hour and psuedo MPG calculation.

[chuck172]

Low rears and big tires have to kill mpg. I have stock, 215/75/R15 with a 3.07 rear. As soon as I put on the tires, everything seemed to really smooth out. Less friction.

[sharpxmen]

Low rears and big tires have to kill mpg. I have stock, 215/75/R15 with a 3.07 rear. As soon as I put on the tires, everything seemed to really smooth out. Less friction.

did you use to have bigger tires? what size?

btw, it's not the friction, it's the weight and wind resistance that counts the most (big tire=taller Jeep, wider tires, more tire sticking out=more frontal area) the friction part of the rolling tire is negligible - but yes, you get way better mpg with stock tires.

[Bounty Hunter]

Low rears and big tires have to kill mpg.

Not necessarily.  Keeping the engine from lugging is very important.  I've consistently had 17+mpg with 35" tires and 5.38 gears.

[DanMarino]

Stock I get 21-24 depending on how much highway driving I do around Baltimore/Washington.  I'd say I'm normally 22 or 23 mpg.  4 angry squirrels, 5 speed, stock tires and gearing.

[Jeffy]

So here's an update on my Jeep.  With the A/C and driving from SF to Bakersfield on hwy 99 I made 20.6 mpg driving at the speed limit or slightly above.  From Bakersfield to Oakhurst, it was again around 20 mpg.  Then driving up hwy 41 which takes you from a few hundred ft to over 5000 ft in a short time (35mph most of the time), to the Yosemite Valley then out on 120 back to I580 I was getting around 16.6-17 mpg.  Still with the A/C on.  Well, until the pump decided not to work anymore and lock up.  But in any case, that's not too bad for a lifted Jeep running 33's and 4.56's at 70-75 mph.  I also had the rear packed with tools, water, and a lot of other things.  So, not too bad.  It was only a little bit more tiring then driving a car.

[jfrabat]

So here's an update on my Jeep.  With the A/C and driving from SF to Bakersfield on hwy 99 I made 20.6 mpg driving at the speed limit or slightly above.  From Bakersfield to Oakhurst, it was again around 20 mpg.  Then driving up hwy 41 which takes you from a few hundred ft to over 5000 ft in a short time (35mph most of the time), to the Yosemite Valley then out on 120 back to I580 I was getting around 16.6-17 mpg.  Still with the A/C on.  Well, until the pump decided not to work anymore and lock up.  But in any case, that's not too bad for a lifted Jeep running 33's and 4.56's at 70-75 mph.  I also had the rear packed with tools, water, and a lot of other things.  So, not too bad.  It was only a little bit more tiring then driving a car.

That's actually quite good.  I am lucky to get 15 mpg out of mine!

[95yj]

on the hwy I am getting 18-20 doing 70mph. 2.5L with 31" tires. I do have a cracked exhaust manifold and a patched mid pipe that leaks like a sieve. Hopefully after I get that fixed i will see some better mpg

[chrisfranklin]

Mine is still about 15mpg city/17 mpg highway with 4:10 gears and 31" MTs. 

My tires are holding up decently and it's going to be awhile before wear forces me to change them.   But if I moved up to some skinny 33s at some point, I'd probably do 4:88s and I wouldn't be surprised if my mileage numbers stayed around the same as now. 

I've been keeping the top off year around and using a cab-cover for when it's parked -- topless driving admittedly probably doesn't help with the aerodynamics. 

[sharpxmen]

i'm between 14.5 and 15.5 if i drive normal, stepping on it gets me to 13s

[jfrabat]

LAst time I checked, I was back to 14 mpg's, which is REALLy good for my rig (the best I have gotten out of her EVER was 15, and that was with no lift, no winch, no aftermarket bumpers and 31's!).