Tj gas mileage

[smithmonsters]

What do all you other tj owners get gas milage wise? I have a 2000 tj with 30,000 miles and on 14.2 gallons of petro i can only go about 150 miles. I know my odometer is off but does that seem like a joke or is that normal? I have a K&N filter and a throttle body spacer. Running 35 12.50 X-terrains. Do i need a tune up or exhuast or what? Thanks

 

[SmokinCamel]

I also have a 2000. I run the 4.0L and 33's. I avg about 14-15 MPG. I can go about 230 miles on a tank.

 

[BlackSheep]

Those gears for the speedo aren't that expensive. I paid about $10 for mine from the jeep dealership on state street just north of the interstate. I've not done any mileage calculations lately, but that is because most of my driving is on the trial. I'm sure I'm not getting great mileage, but I didn't buy it because it is an economy car.

 

[smithmonsters]

Yeah I know its not a economy car. I know i need to gear it but I dont want to put money into crappy axels. So i need to wait till i run across a tj 44 or build a 60.

 

[RockMonkey]

Turn on a GPS, drive a bunch of miles, and find out how far you are really going. My 97 TJ 4 cylinder with stock (4.10) gears and 33s gets about 20 MPG. That's down several miles from the 30 inch tires it came with, but really not bad.

 

[pokeyYJ]

I get about 17mpg in my 98 TJ 4.0 with 33's, mostly freeway driving

 

[Farmer Jed]

Last time I bothered to check, I got around 16mpg with approx. 75% city driving.

03 TJ, 4.0L, auto, 4.10 gears, 33" MTRs

 

[Underdog]

I used to get about 15 in my 98 with 3.73 gears and 33 MTR's. Recently I noticed it has gone down quite a bit. Would the crack I have going halfway through my exhaust manifold cause this? I am replacing it with a Banks this weekend and hope to see some improvement.

 

[Badcop]

2 tricks I noticed, I drove my 02' from Anchorage AK to Ogden, got aorund 20-22 depending on headwind with a 1600lb trailer running 35's and 4.10's and a JET. Without the JET in I pull aorund 17-19. In town anywhere from 15-17.

1. Take the gas tank out and remove the "gooseneck" style fill tube. Prevents you form having a 19 gallon tank.

2. Put a good K&N in it and remove the upspout form the filter box.

Also with 35's and and 4.10's my speedos off by 10 higher than actual. 35mph is actual 25. (thanks Garmin)

 

[Underdog]

Thanks for the info. I installed the banks this weekend and will see how that does, then I will start with changing the airfilter and go on from there. Does anyone know how far off I can expect my milage to be. Like I said I have a 98 Sahara with 33x21.5x15 MTR's and 3.73 gears (stock). The stock tires would have been 29's. Is there a calculator anyone knows of to see how far off the odometer is?

 

[BlackSheep]

You can take the ratio of the tire sizes and that will give you a pretty good idea. If you can find the actual revolutions per mile for the tire that is actually a bit more accurate.

I looked on Goodyear's website, and they don't show the actual RPM, but they do show the overall diameter of the tire. The best I could find as far as original equipment is the Wrangler GS-A. It has an OD of 28.3"

Goodyear's site kind of blows, so I went to tirerack.com and found the 33x12.5R15 MT/R has an overall diameter of 32.4"

so, if you take 32.4 and divide by 28.3 you get 1.1448.....

all you need to do is multiply your indicated speed by 1.14 to get your actual speed. Or, for distance travelled, multiply your indicated distance by 1.14.

 

[Bud]

Back pressure from the exhast can change your MPG, but it sounds mostly like a gearing problem. If it'll be a while until you get the newer axles then just get gears now, and sell your loaded axles later on this site. You'll still get decent money back and it'll help the next guy get from where you're at. They could buy your complete axles and install them at home, plus have extra shafts from their original axles. Check your fuel filter, if one is mount outside of the tank and clean out the fuel injectors. I also found in one tank I worked on that the pick up tube was cracked in the tank and it was getting terrible gas mileage

 

[Bart]

I get unbelievable mileage in my 97 TJ. I've had it for almost 2 years and am still on the first tank of gas. Someday I'm actually going to start it and all that will change.
Bart

 

[Underdog]

After installing the header and cleaning the fuel injectors, I have seen quite an improvement already, (the injectors were nasty). Using Blacksheeps (1.14) I am currently getting close to 16 MPG . I have also heard that removing the gooseneck from the intake will increase the MPG slightly, has anyone else tried this. I am going to pull it off and see if there is any increase.

 

[Badcop]

I have also heard that removing the gooseneck from the intake will increase the MPG slightly, has anyone else tried this. I am going to pull it off and see if there is any increase.

I dont know about mileage increase or how it would affect the engines performance, but it will allow you to go further onj a full tank.

 

[ryslc]

i use about two tanks a year in my tj, it does great

 

[Underdog]

I dont know about mileage increase or how it would affect the engines performance, but it will allow you to go further onj a full tank.

The Gooseneck I was refering to is the one on the intake box not the one in the gas tank. (is will try the gas tank one when I change the filter) I pulled out the "intake gooseneck" and the hole is a lot bigger, not sure how much this will help but I will post if there is any increase.

 

[Badcop]

Well then I stand retarded.