PDA

View Full Version : gas mileage???



Jpdst29
04-03-2005, 09:36 PM
with the prices of gas soaring...i figured it was time to become anal about the gas mileage of my ZJ

it has the 4.0 I6 engine so it isnt exactly a gas hog...but i do have some questions anyways...

1. i have a decent sized exhaust leak in my header...would this contribute to a lower average gas mileage?

2. i have the onboard computer that tells me my average miles per gallon...mine reads 16.5mpg...i was just wondering if this was good or not compared to other peoples out there...and also is this computer reading accurate or should i go back to the old method of figuring out my MPG by hand...

either way...i think it is time to invest in a good gas conserving vehicle to offset the cost of the gas the ZJ consumes...got any ideas???

later

2002wranglerX
04-03-2005, 09:51 PM
honestly, find a 500 dollar honda. you're going to spend way more than that into mods and you're going to get a few more MPG.

just my .o2

Bill
04-03-2005, 10:24 PM
My Jeep sucks in the MPG department... I did pretty good last tank though, a 13.86 MPG, that very good for me!

OverkillZJ
04-03-2005, 11:00 PM
16.5 on a stock ZJ is not bad by any means. That header could be contributing but since your ZJ is getting average ZJ MPG anyway, who knows. I get more in my jeep but that's due to the right gearing + intake + exhaust and the fact that every sensor and plug and such is pretty much new.

If you're really looking at not paying out the ass for gas, make the ZJ a trail rig and get a honda / yota...

JeepGeneral
04-03-2005, 11:30 PM
I thought about a 500 dollar Honda, however it usually turns into a 1000 dollar or more honda come inspection time.

Jpdst29
04-04-2005, 05:51 AM
getting the 500 dollar honda doesnt sound like a bad idea...thanks guys...

leonw
04-04-2005, 09:23 AM
Yeah, 16.5 is good. I have the 4.0 with header, catback, Turbo City Intake 3.55 gears and 31's. I get 14.7 around town driving normally, er... let's say responsibly. Sometimes I drive it harder to feel and hear the performance mods working. I can drive the mileage down to 12 or 13 doing that or towing my boat. What kills us around here...HILLS!!! Did you ever watch the mileage mode that shows mileage at that instant? Every time mine downshifts, it really starts guzzling. Forgive me if this sounds like an oversimplification, but what helps me is try to gradually pick up speed going into hills that you know it will downshift on. The more you can keep it from kicking down the better your mileage will be. I watch my tach more than the speedo. When I travel somewhere flat, I can push 20mpg and that's with a safari rack hindering my airflow. I would love to re gear but I just sunk my jeep money into the TJ and have to start saving again. I think the computer is fairly accurate. I had an exhaust leak too, you should replace that. You can pick up a performance header for less than the stock manifold that is prone to cracking. At the least, get the exhaust manifolds with the flex bends where the cracks always occur. I had one once on a jeep, got it on ebay for about 13O bucks.

And yes, you can spend hundreds upon hundreds in performance mods, and you are lucky if you gain 2mpg total. My goal was to try and compensate for bigger tires and for making it less aerodynamic. I got closer to where I was in stock form but not quite. 4.11's would get me there. You gotta ask yourself, is it worth it? How much time to get a return on those purchases? Probably never.

My next Grand Cherokee may be a WJ with a 4.7. That's what our company car is and I get better mileage in that than I do with my I6. If I drive it gently, I can get up to 19-20.

Jpdst29
04-04-2005, 03:57 PM
Yeah, 16.5 is good. I have the 4.0 with header, catback, Turbo City Intake 3.55 gears and 31's. I get 14.7 around town driving normally, er... let's say responsibly. Sometimes I drive it harder to feel and hear the performance mods working. I can drive the mileage down to 12 or 13 doing that or towing my boat. What kills us around here...HILLS!!! Did you ever watch the mileage mode that shows mileage at that instant? Every time mine downshifts, it really starts guzzling. Forgive me if this sounds like an oversimplification, but what helps me is try to gradually pick up speed going into hills that you know it will downshift on. The more you can keep it from kicking down the better your mileage will be. I watch my tach more than the speedo. When I travel somewhere flat, I can push 20mpg and that's with a safari rack hindering my airflow. I would love to re gear but I just sunk my jeep money into the TJ and have to start saving again. I think the computer is fairly accurate. I had an exhaust leak too, you should replace that. You can pick up a performance header for less than the stock manifold that is prone to cracking. At the least, get the exhaust manifolds with the flex bends where the cracks always occur. I had one once on a jeep, got it on ebay for about 13O bucks.

And yes, you can spend hundreds upon hundreds in performance mods, and you are lucky if you gain 2mpg total. My goal was to try and compensate for bigger tires and for making it less aerodynamic. I got closer to where I was in stock form but not quite. 4.11's would get me there. You gotta ask yourself, is it worth it? How much time to get a return on those purchases? Probably never.

My next Grand Cherokee may be a WJ with a 4.7. That's what our company car is and I get better mileage in that than I do with my I6. If I drive it gently, I can get up to 19-20.

excellent information...thank you!!!

RedneckYJ95
04-07-2005, 10:02 AM
My YJ with the 4.0 and 3.07 gears gets 10mpg. Feel better now? At least it has the 20gal tank to make it seem like I don't need gas as often. :lol:

leonw
04-07-2005, 01:50 PM
I refuse to figure out my mileage for the TJ. I'm guessing 12-13 but ignorance is bliss. Hopefully it's not worse.

The dang ZJ has that computer so I look at it, because it's there. I oughta put electrical tape over it.

danzay
04-12-2005, 11:23 AM
my zj gets 12 mpg. it has 33 x 14x 15 super swamper boggers on it with 4.10 gears. it would do a lot better with smaller width tires

OverkillZJ
04-12-2005, 11:28 AM
It's really ironic that my big ZJ does so much better than most rigs :lol:

Unless I get on it, then it's 2MPG

Cebby
04-12-2005, 11:39 AM
16.5 is good. My WJ with 3.55's and 31's is about 15 around town. Highway is much better - probably better than I realize since my speedo seems to be off quite a bit now...

Bill
04-12-2005, 12:10 PM
The TJ has been getting about 12.6 MPG for the last 2 fill-ups, but the H2 I have been driving is getting a whopping 10.3 MPG. :wink:

It is sad when the TJ is doing better than anything else you are driving.

The motorcycle got in the 35-40 MPG range, and the new bike is yet to be determined. 8)

cjw94xk
04-12-2005, 05:22 PM
I calculated my mpg the other night. No
t good. 11.4, and I am running mostly stock with the exception of a tbs and cold air. On the other hand, all I have been doing is driving short distances back and forth to school, and living up here in Mt. Washington. Seems like all I do is go UP hills. lol