Test Drove a JK Today...
- Thread starter Dave Bennett
- Start date
prepmech
Observer
My step-dad gets 18.5 mpg in his JK unlimited sahara, but it is really slow. I've driven it a few times and have been very disappointed, so much that I have decided against buying one. The interior felt cheap to me, and the whole thing had too much plastic on it. The new axles sounded great, until they started having problems with the housings breaking. I ended up getting a WJ to drive for now, waiting for Jeep to fix the issues with the JK before I buy one.
Scott Brady
Founder
I think anyone who goes from a I6 4.0L to the 3.8L will be a bit disappointed in the power, but it really is way more then adequate and I have seen a constant 17 mpg average (on the gauge) and nearly 20 driving it down from Denver. That is the trade-off.
If you changed from a gen one Tacoma or older Toyota truck, it will feel downright peppy. If you changed from a Land Cruiser, it will feel like a sports car.
It is all perspective...
If you changed from a gen one Tacoma or older Toyota truck, it will feel downright peppy. If you changed from a Land Cruiser, it will feel like a sports car.
It is all perspective...
Bergger
Explorer
expeditionswest said:
I agree completely. My neighbor just bought a JK Unlimited and I test drove it the other day. I've been driving an 03 Tacoma with the 3.4 for the past 5 years and the JK is very comparable to it as far as power. Scott I don't know if I would call it "peppy" in comparison but definitely in the same ballpark. For me I would be completely satisfied with it on the hwy, even here in Colorado. Couple that with up to a 73:1 crawl ratio in the Rubicon and I don't think anyone will have any issues off road. I have no plans to get rid of the Tacoma for at least the next 5 years, told myself I'd have it for 10 when I bought it, but I did try to talk the wife into trading the Xterra for one. She said no and she's the voice of reason. And it makes sense not to. The Xterra is our long distance road trip/light off road vehicle and there is no comparison between the Xterra and the JK in those areas.
Gear
Explorer, Overland Certified OC0020
Uticon
Well I think I should bring the MPG back down to my reality. I have an 07 JK automatic with 5:13 gears and 315/75/16(35" Goodyear MTR's) The only engine modification is an AFE air filter. Here are my current numbers from the Scan Gauge II.
255 miles traveled
29 miles per hour average
8.6 hours of driving
18.4 gallons of unleaded 87 gas used
Drum roll please :rockon:
13.8 miles per gallon.
Oh and if I drive any slower my wife is going to shot me!!!!
Well I think I should bring the MPG back down to my reality. I have an 07 JK automatic with 5:13 gears and 315/75/16(35" Goodyear MTR's) The only engine modification is an AFE air filter. Here are my current numbers from the Scan Gauge II.
255 miles traveled
29 miles per hour average
8.6 hours of driving
18.4 gallons of unleaded 87 gas used
Drum roll please :rockon:
13.8 miles per gallon.
Oh and if I drive any slower my wife is going to shot me!!!!
Last edited:
TheGillz
Explorer
MPG, computer says 16ish in town, 21ish on the highway, any time I have cross referenced it with actually comparing a fill up with miles traveled, its consistantly 3mpg less than the computer thinks.
We took a trip across Idaho a couple weeks ago and I'll post what I posted about it on the jeep forum I go to:
This was about the estimator feature, but illustrates the point. This trip was 15% off road/dirt road, 20% Freeway, and 65% state highway.
We took a trip across Idaho a couple weeks ago and I'll post what I posted about it on the jeep forum I go to:
This was about the estimator feature, but illustrates the point. This trip was 15% off road/dirt road, 20% Freeway, and 65% state highway.
TheGillz
Explorer
MPG, computer says 16ish in town, 19ish on the highway, any time I have cross referenced it with actually comparing a fill up with miles traveled, its consistantly 3mpg less than the computer thinks.
We took a trip across Idaho a couple weeks ago and I'll post what I posted about it on the jeep forum I go to:
This was about the estimator feature, but illustrates the point. This trip was 15% off road/dirt road, 20% Freeway, and 65% state highway.
We took a trip across Idaho a couple weeks ago and I'll post what I posted about it on the jeep forum I go to:
This was about the estimator feature, but illustrates the point. This trip was 15% off road/dirt road, 20% Freeway, and 65% state highway.
MuddyMudskipper
Camp Ninja
expeditionswest said:
.....and if you changed from a solid axle Land Rover it will feel like Thrust SSC.
durango_60
Explorer
expeditionswest said:
Absolutely, coming out of my 60 I am giddy about going 65 up the passes!:roost:
If all we had to compare to was the Model A Ford, no doubt the current V-6 would seem outright flexy. However, there are any number of excellent power plants in the world these days, so while the amount of available power in any given vehicle is a matter of personal perspective, I think all of our perspectives, individually and collectively, indicate that the current Jeep is under-powered. Certainly no one is raving about the smokin' power of the V-6.
Besides, nearly all of the discussion so far has been about this vehicle on the road. Fair enough since that is where nearly all Jeeps are driven these days. But an engine that delivers adequate power for highway driving will likely deliver the wrong kind of power for off road use, gearing notwithstanding. The current V-6, on paper, makes good power and reasonable torque. Where in the power band does it produce its power? I believe the reason most folks feel the power is missing is because the power that the engine makes, is made too far up the rpm band.
Low end power is more important to off road use, and also contributes heavily to the "feeling" of power under most circumstances. The only way to get that power is with displacement or the rotating mass of a diesel. To a limited extent, Jeep came up with a very fair compromise back in the 60's with the 225 Buick V-6, which coincidentally is 3.7L. They did this by mounting a 52 pound flywheel, which stores enormous energy that makes the motor feel more torquey than it really is, but the engine still makes its power and torque far lower in the rpm range than today's modern versions of the same size engine. This is attributable to the cam and the fact that the old Buick motor is not emission controlled. The result is closer to today's small displacement diesel in terms of how and how much power it produces. Because of the cam timing, the Buick flattens out at about 3,500 rpm, at about the same point that the modern V-6 starts to pull hard.
My new Nissan Frontier suffers from this same problem. It may make more HP than any truck in its class, but the power peak is up there around 3,500rpm to 4,000rpm, way too high for sensible use off road. I have a feeling that the horsepower output at, say 1,600rpm, is down around 50hp. Even with the automatic and low range, it will hardly get out of its own way in difficult terrain. I, too, would say the power is "adequate" but it is certainly nothing to write home about either, and I would rather have more of the 265hp down low where I could use it without standing on the gas. It wouldn't be as brisk while passing at 85mph on the interstate, but it would perform much better otherwise.
Perhaps it is possible to modify the Jeep engine to bring the power down to a more usable range. "De-tune" it so to speak.
Besides, nearly all of the discussion so far has been about this vehicle on the road. Fair enough since that is where nearly all Jeeps are driven these days. But an engine that delivers adequate power for highway driving will likely deliver the wrong kind of power for off road use, gearing notwithstanding. The current V-6, on paper, makes good power and reasonable torque. Where in the power band does it produce its power? I believe the reason most folks feel the power is missing is because the power that the engine makes, is made too far up the rpm band.
Low end power is more important to off road use, and also contributes heavily to the "feeling" of power under most circumstances. The only way to get that power is with displacement or the rotating mass of a diesel. To a limited extent, Jeep came up with a very fair compromise back in the 60's with the 225 Buick V-6, which coincidentally is 3.7L. They did this by mounting a 52 pound flywheel, which stores enormous energy that makes the motor feel more torquey than it really is, but the engine still makes its power and torque far lower in the rpm range than today's modern versions of the same size engine. This is attributable to the cam and the fact that the old Buick motor is not emission controlled. The result is closer to today's small displacement diesel in terms of how and how much power it produces. Because of the cam timing, the Buick flattens out at about 3,500 rpm, at about the same point that the modern V-6 starts to pull hard.
My new Nissan Frontier suffers from this same problem. It may make more HP than any truck in its class, but the power peak is up there around 3,500rpm to 4,000rpm, way too high for sensible use off road. I have a feeling that the horsepower output at, say 1,600rpm, is down around 50hp. Even with the automatic and low range, it will hardly get out of its own way in difficult terrain. I, too, would say the power is "adequate" but it is certainly nothing to write home about either, and I would rather have more of the 265hp down low where I could use it without standing on the gas. It wouldn't be as brisk while passing at 85mph on the interstate, but it would perform much better otherwise.
Perhaps it is possible to modify the Jeep engine to bring the power down to a more usable range. "De-tune" it so to speak.