I'm on my 6th Jeep and this engine is great. I actually test-drove it before I bought it, so I knew what I was getting.

 

The only time I haven't been OK with the engine is on the interstate if it's windy.

 

Don't get me wrong I would buy it again because of what my jeep can do. However, if there is one thing jeep could do to improve it in my opinion would be a better engine with low end torque.

The 4.2L I6 in my CJ hits max torque at 1600 RPM. That means you have max tire turning power at just twice idle rpm. That's the power I am used to and what I would like in my JK.

 

I kinda like the engine, too. I'm slap happy with mine.

 

I think my problem is I just came out of a 4wd truck with a V8 so I have no true comparison.
To me the JK seems very weak.

 

My unlimited with auto and 3.73 is excellent. Climbs MUCH better than my YJ, Lower rpm, no wheelspin. These long jeeps really do well...

 

I love mine I have a 2dr with a 6sd and 4.10 gears. I just put on 35's so we'll see after alittle time what I think but after gettin rid of a YJ with a 4cyl and 35's I can't complain at all.

 

On a two-door, with 4.10's and stock tires, it does just fine. I can see where after adding a bunch of weight and gear where it would get to be more unpleasant (especially on an Unlimited). Personally I don't mind it though.

 

I like the 3.8 but I think the 4.0 was a better engine.

 

With the CAI, Magnaflow exhaust, and the Hypertech running 93 octane I find the 3.8 acceptable. Stock, it is a little sluggish on the highways,and off the line. I would prefer the diesel also for the torque and fuel economy.