Rickster

Hi guys , Just a basic question,
I have a 1998 Jeep Cherokee sport w 4.0 ltr AT with 235,000 klms. (141,000mls). Lt235x75x15 tires, Platinum plugs (which work really well) a K&N factory style filter ,new performance wires,cap and rotor. Use Lucas oil, w/Fram oil filter and I run injector cleaner every 2nd tank on mid grade fuel.
Now here is the question: Is there anything else I can do to improve gas mileage? I get approx 325-370 klms to a tank or 200-220 miles .
Is that good? I also heard of a guy who changed his trans to one that had an extra overdrive. but it didn't say if it was a jeep tranny of something else.
Any thoughts or ideas ? Thanks
P.S. I just read that someone changed injectors from a 2.5 Sebring and went from 12.5 mpg to 17.5?

FASTMETAL

i usually get about 320 to 350 with my jeep, engine wise its all stock,, it has 31" tires on it,, maybe i should try what you did haha

quinnt

I get about the same, 200ish a tank. I have a 3 inch lift and 31 inch m/ts

89Laredo

You spend all the money on lucas oil and run a FRAM filter?!
At least run a Wix/Purolator...

also, most 4.0s dont like the platinum plugs. Most people get better results with champion copper.

NewXJaddict

I can't say much about gas mileage but I would worry about having that fram filter on there. Heard too many stories about fram. I am glad I found out about the problems with fram and got rid of the one that was on mine before anything happened.

Napa gold (wix) is what I am running from here on in now.

Rickster

Well ,I don't know where you are but I get Lucas oil cheaper then Castrol oil
and i run (because of the high mileage) 15x20w in summer and Castrol 5x30w in winter. as for the Fram filter it's also for high mileage, I haven't anything bad about them yet? Let me know.. tnx. and I tryed Nkgs before (not bad) and I have nothing but troubles with Champions on any of my vehicles.

89Laredo

Lucas is 6$ a quart here for conventional. I thought it was more than that, had to look it up. Still expensive compaired to my 12$ jug of oil.

Frams have cardboard endcaps that are known to get holes, or come undone allowing unfiltered oil to pass.

Why do you run the thinner oil in summer and thicker in winter? that makes no sense..

Also, you dont need to run injector cleaner that often. Every oil change should do it.

R Cannon

I get over 300 miles from my 95 5speed. I cant figure it out. try seafoam. A lighter right foot helps. Ive heard MSD boxes may help. Do a good search on the injectors. Yes they are supposed to help. Are you using the A/C?

Rickster

Umm! sorry. i didn't make myself clear i run Lucas 15x40w in summer (highway truck oil) and Castrol 5x30w in winter. Here I get a 4.4 liter jug of Lucas for $12.99 cad and tnx for the info on fram.
I looked at your pics you have a fram filter too. well i guess we both should change.
I ran injector cleaner every 2nd tank for about 2 months now once a month.
I like the injector swap idea will have to look into it.

Metmknice

Better oil filter, different plugs, some better injectors. Will probably help mileage. For winter, depending oh hold cold it gets, I can see using a 5w vs a 10w, but the true oil weight should be the same.

89Laredo

I stopped using fram a while time ago, that pic was taken after my first ever oil change.
I see what you did, you wrote 20 instead of 40. That makes alot more sense and is kinda like what I run (15w40 Ford diesel oil summer, 5w30 valvoline maxlife winter.)

Rickster

I think your still getting better then me , your talking miles right ,i only get about max 220ish per tank compared to your 350(sigh) i think I'll try injector idea.

Rickster

I wish i would have kept that article on the tranny swap! the injector idea is easier though.

CodeXJ

I get 220 with city driving, which is about 18mpg. On the highway it goes a bit further, I don't remember the distance but the last time I did a lot of highway driving it got 23-24 mpg. 193k miles, cheap-o plugs (Autolite or NGK, can't recall. They were like $1.99 a pop though), standard air filter, standard wires/cap/rotor.

Doesn't help that I have a bit of a lead foot, though.

Rickster

HaHa!! how can you not! these jeep can be real zippy. I'm looking foreword to the new Trailhawk Now that's class! posted some pics , check it.