rediculous gas mileage

[Blair Code]

My milage for the second half of last week was:

Distance travelled: 416 Km
Amount of gas required: 53  Litres
Metric (Canada) 12.74 L/100KM
Metric (Europe) 7.85 KM/L
US Gallons 18.57 MPG
Imperial Gallons 22.17 MPG

2001 Stock TJ Sahara, 4L, 5 speed, Tires 235 Long Trail TA on 16" rims.
This was real mixed driving downtown daily, plus HWY and rural roads.

I expect the milage to go down next year if I can afford some modification. Any recomondatios for rear end gears if I move to 31" tires. I am planing to keep one set of street tires on rims for the week and a second set of mud tires for the weekend.

What is the best milage I can expect out of a 4L? Is any other 4L. geting beter milage?

[redbull]

Any recomondatios for rear end gears if I move to 31" tires.

What gears do you have now? I'm on 31"s and have 3.08 gears, which turns 5th gear into overdrive - no hills or headwinds. I'm looking for 4:10s from a 4 cylinder.

[Blair Code]

I have not confirmed what I have curently for rear end gears. The rear end is stock, as far as I know. I have the same problem on hills even with the 4L, unless I hit a hill at 120Km+ in 5th I start to drop a lot of speed. I think if I put lower gears in then fith will be more usefull and I will be able to run in ii more often.

If  I go form 29" tires to 31" what change of gears would keep things the same and what would lower the ratio and make 5th more usefull?
 

Blair

[Blair Code]

I have not confirmed what I have curently for rear end gears. The rear end is stock, as far as I know. I have the same problem on hills even with the 4L, unless I hit a hill at 120Km+ in 5th I start to drop a lot of speed. I think if I put lower gears in then fith will be more usefull and I will be able to run in ii more often.

If  I go form 29" tires to 31" what change of gears would keep things the same and what would lower the ratio and make 5th more usefull?
 

Blair

[blackrube]

i use 33 inch tires with 4.10's and can still use 5th  no problem,,so wouldnt worry to much about changing gears for 31,s

[HBZ]

What is the RPM @ 60mph in 4th?

[BlackYJ]

With my 4 banger, 4.10s and 31s I usually get 400-425 km in the city and 500-525 on the highway if i push it.

I would not recommend a 4.0L, 31s and 4.10.  It will be too low.  Talk to a rubicon owner and see what their mileage is

[4low]

BlackYJ,

what speed are you going on the highway?

I can get about 400-430kms in the city, but if I get on the highway @ 110 It's down!!! To like 350 kms a tank.....

[Chandro]

well here's your Rubi reply

might as well start off with my specs...

'03 Rubi with 4" lift and 33X14.5X15 TSL's
Aftermarket front and rear bumpers
winch
quick discos
onboard air
CB
and about 40lbs of recovery gear.

sadly by the looks of it i think i get more km out of a tank of gas on my street bike  I don't have any real figures for you as i just bought it a couple of days ago and have only filled it once.  btw this is my first post Hello All!  so yeah. i figure i am going to MAYBE get 250km out of a tank of gas  :evil:  but what do u do...going to take it to dodge and get a tune up and see if that helps...hopefully lol

[Bnine]

Specs : 88 YJ 4.2L(258)

 Is there anything i can do to help it?

Not really Paul.

We are all driving a 50 some year old motor. They just dont get great milage.

You could regear to operate at a better torque range, convert to fuel injection. Do about 10 other mods that claim milage increases which are really blowing smoke. ie, headers, intake, high power ignition, wear darker sunglasses, etc etc etc. Most of it is BS, and the very slight gains in milage never actually pay out.

But even with all that, it really wont change by any significant amount. Couple mpg if you are lucky.

The biggest mpg factor to jeeps is high speeds on the highway cause they are a box. Other then that, they just dont vary by much.

[Bnine]

With my 4 banger, 4.10s and 31s I usually get 400-425 km in the city and 500-525 on the highway if i push it.

I would not recommend a 4.0L, 31s and 4.10.  It will be too low.  Talk to a rubicon owner and see what their mileage is

Most rubs average between 14-17mpg depending on how modded they are.

Thats with being at least 500lbs heavier then a sport when they are stock.

4.10''s an 31's is about right. Still a bit weak.

Better milage would be 4.56's, 31's, staying at or under 90kph.

[cLAY]

With my '89 XJ and 5spd I got close to the same milage with 31s and 4.10s as I did with 215s and 3.08s. But I had lots more power, on street and trail. With the 3.08s and 215s I almost always had to downshift or hold the pedal right to the floor to maintain speed on any kind of hill. With the 4.10s/31s I did not need to downshift nearly as much. I think the stock 3.08 gears are way too overdriven for a Jeep.

[Win94]

I had O2 problems, well I had no O2

.....................wouldn't you have a check engine light come on if the o2 sensor was bad???

[Win94]

500-525 on the highway if i push it

...................Black YJ i seriously doubt you get a 500km range witha full tank in your YJ.  If you posted this on www.jeepforum.com you would seriously get challenged by a ton of die hard jeepers.  I don't think a distance of 500 kms could be achieved even if you were doing a paltry 60 kms/hour on the highway. :roll:

[Asia]

On a recent trip to Waiparous from Calgary with some off roading ( Lost Knife and Meadow Creek trails ), back home and some city driving my fuel consumption was 15.7 L / 100 km.   '95 YJ, 2.5 L, stock 4.10 gearing, 2.5" lift, 31" M/Ts, winch, hard top, rock crawler rear bumper, rear locker, some tools and recovery gear, recent cleaning of the K&N, and plugs changed in the spring.  Cruising @ 100 - 110 km/hr on the highway.  It has been better and worse.