97 TJ gas mileage
- Thread starter nutznky
- Start date
But what gear ratio does yours have? Most people don't know that in the 97 TJ with the 4cyl. they also used a 3.55 gear ratio in some and a 4.10 in others. That was the only TJ they did this in if I'm not mistaken. I know it's not gonna get 17-18 mpg, but I was thinking maybe 14-15. Especially with the chip, cold air and aftermarket exhaust. Keep chiming in here guys. Someone on here is running a similar setup I'm sure.
That vehicle stock has an EPA combined rating of 18 mpg:
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I would expect the performance chip to use more gas instead of less (granted I don't know much about them). Add the big tires to a 15 year old truck and I'd guess you're in the 12-14 mpg range.
So what mpg are you getting, and how long have you tracked it? I record milage and fillups using fuelly and pull 14.4 mpg on my 2005.
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I would expect the performance chip to use more gas instead of less (granted I don't know much about them). Add the big tires to a 15 year old truck and I'd guess you're in the 12-14 mpg range.
So what mpg are you getting, and how long have you tracked it? I record milage and fillups using fuelly and pull 14.4 mpg on my 2005.
clemtiger8
New member
I have the 4.0 tj 4" suspension 3"body 35" tires 4.10 gear front and rear. Believe it or not i get 22mpg. You should get 13-15.
All the charts I'm pulling up say with 35s and 4.10 gears It should get better fuel economy than stock but less power to the rear wheels. At 65 mph it should run at 2500 rpms which is close to what my silverado runs at that speed and it has 4.10s in it. 4.56s is what it calls for to put it back to stock and compensate for the tires at which point it would then run at 2800 rpms at 65 mph. If this is the case then running at the same speed at 300 less rpms would have to be more efficient but takes it out of its powerband for towing capacity and overall power.
Here is the website with the chart if anyone else needs to get an idea. http://www.jeep4x4center.com/jeep-tires/tire-gear-ratio-chart.htm
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JohnnyO
New member
Our 97 is a 4-banger with a 3 speed automatic, what I think are 4.10 gears based on the charts I've seen. Spins 3000 rpm at 70 mph. No lift, 235/75-15 tires, and averages about 13 mpg. On-road the 4-bangers don't get any better mileage than the 6's. Off-road the 4-bangers use much less gas.
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Danny in Galveston
New member
The 4-banger TJ with 5-speed came with 4.10 gears. With those big tires and no re-gearing, your engine will be in a bind and mileage will suffer. When I bought my 2001 it had 31" Mud Brutes. 5th gear was practically useless and in-town mileage was better than highway, 15 and 13 respectively. I now have 28's and get about 16.5 in town and 19 on the highway.
