CHRONIC_2001_XJ

So I drive a 2001 Cherokee Sport. It has a 3 inch lift and 31 inch all terrain tires. Modest exhaust upgrade w/cat and cold air intake. I think my tank is 17 gallons.

I'm only getting about 200-210 miles per tank ...about 12 mpg city. I recently sold my 96 Cherokee sport and I got about 260-280 per tank about 17 mpg with same mods...no lift.

Is this expected? It seems significantly lower. Will tires and lift affect it that much? I'm slightly concerned that its not running efficiently...I'd like to get at least 15mpg.

Any thoughts on this would be appreciated!

89Renix

If im assuming correctly you still have the stock 3.55 gears??? there has to be something wrong, i stand by seafoam, but some people hate it... id say give it a try..

Im running 35x12.50 on stock 3.55 gears and im getting about 9-11 mpg city

CHRONIC_2001_XJ

yeah...stock rear end. I'll look into seafoam. I'm also going to change spark plugs.

LeRoy90laredo

i was under the impression all xj's had a 20 gallon tank.

im on 30's and i get 16-18 miles to the gallon(mixed city&freeway) but i drive it like a granny to get that mileage.
i would try a seafoam treatment/injector cleaner.
they also sell oil additives that "renew" an engine. it takes the place of a quart of oil.
all are things to look into as well as lightening up on the pedal a little.

with 31's alot of people recommend 4.10 gearing.

good luck man

89Renix

X2 on 4.10s but i disagree with the lightening of the foot on the pedal :P

but then again i need it, 35's + 3.55s =

CHRONIC_2001_XJ

Thats even worse if they are 20 gallons. I last drove until I though I was gonna run out of gas and I filled up only 16 and half gallons. I could be wrong.

I'm never light on the pedal on any car I drive...I'm still getting ****ty mpg.

LeRoy90laredo

on my build sheet from the dealer it reads that we have a 20.9 gallon tank.
that is bad mileage though.
try a tune-up and treatment products like seafoam.

austinjoe13

Do you have a check engine light on? Or are there any unusual noises?

CHRONIC_2001_XJ

No check engine light or anything. I do get a high pitch whistling sound after a couple miles of driving. It only makes the sound when I let off the gas. As soon as I apply any pressure the the gas pedal it goes away.

I made a thread a while back about the noise...some one suggested that I tighten down my intake manifold. I have yet to do that as its 12 degrees outside.

djlarroc

Hmmm.. well, I just recently bought a '97 xj auto 4.0, stock on 225s. I drive about 70% city/30% hwy. I drive it like a granny too, and I'm getting 225 miles on my last 2 tanks.

First fill up, I drove on E light for about 10 miles, and topped it off w/14.9 gallons. Second fill up, I topped off as soon as light came on, and got 14.3 gallons. My jeep is giving me about 15.6 mpg. Not good IMO still. I seafoamed when I bought it too.

I've read of people getting good mileage, but they have all been 5 speeds.

Not sure why my tank is only getting 14 gallons.

TheJerm

17-19 mpg every tank with 4.5" lift, 3.55's and 33's

fwiw, my gf has 01, auto, stock axles, 3.5", 32's, no engine mods and 215K miles. I think she gets 15-17 mpg with hers. I just did a basic tune up for it before i handed it over to her last summer but her mileage has decreased (she needs o2 sensors)

Things to look at:
1) Correct your speedo!!!! I notice about .5-.75 mpg difference from when i calculated the % off and added it in, compared to correct speedo.

2) typical tune up, plugs, filters, oil changes PLUS take an hour to clean your throttle body. Remove it, take the IAC sensor off, and clean the crap out of it with TB cleaner.

3) New "good" O2 sensor cause this tells your computer how much fuel is needed.

4) weight and aerodynamics like roof rack and an elephant in the back

Zack92MJ

I have a 3.5 lift 31/75/15 with a roof rack I have 1/4 a tank left and I'm at ~150 mile to the gallons.

(I found out that every 4 miles my jeep goes the trip say I went 3.5)

4 (space) 3.5
____* ______ <-- Ignore the "(space)" I needed to make space to make this an equality.
x (space) 150

600 = 3.5x

171.4 = x

So in my Jeep 150 = 170 "actual" mile

So 170/15 = 11.3

So right now I'm getting about ~11 mpg.

Now yes all of these numbers are round, and I'll post back when I get my actual numbers.

CHRONIC_2001_XJ

Thanks everyone...good to know where everyone one is at on their mpg's. I'm gonna try and give a tune up this week...I'll repost and see if it makes a difference.

austinjoe13

I'd be happy with that mileage for your kind of driving. I get that going to school on the highway. I also get 25+ from time to time on flat open highways 31s with 4" lift and 3.55s!

86jeepmj

my 89 4.0 5 speed get over 20