OK, I now have 23,000 klm on my Sahara (Tow package with 3.73). 8,000 Klm since I put on the 35's. I commute 60+ miles per day on the highway and I pull a trailer a couple times a week with it, up some pretty steep grades and I don't feel the need to regear. In the bottom end there is still more climbing power/torque then my pick-up has, but its a lower speeds. Do the hill test, stop on a very step grade with or with out a trailer and just take off from a dead stop and see how effortless it is for that lowly 3.8 to pull away. This is what it is designed to do. No fancy exhaust, no fancy intake, no power programmer, just all stock.
That being said, I noticed the power issue some after switching to 35" tires but after about 4,000 klm the computer adapted and things smoothed out with less up/downshifting. Keep in mind that the throttle is fly-by-wire and really takes some time to get use too, it doesn't react the same as direct throttle.

My suggestion:
Stick with the stock 4:10 if you are going to stay with the 32" tires.

 

are you going up hill? is it windy? dont forget your arodynamics in a jeep are compaird to a 4x8 sheet of ply-wood

 

Mine has loosened up considerably. Of course, I have the 6 speed, so I'm sure that makes some difference. It just became much more willing to rev and feels stronger all the way through the powerband. I'm really starting to like this motor.

 

Not enough power,
To the floor with the gas pedal, Up with the radio, Let that that tranny work without having to hear it overheat or shift like crazy. Shift down low to let your RPM's soar for more power. Don't you love the "NEW DAYS" where they are dumb enough to give you a lifetime powertrain warranty. The redline on the tac is just to tell your friends How long at how many RPM's it took before the engine went through your hood. YEEEEEEEE HAAAAAAAA


Thanks DM

 

My observations exactly.
I'm at 3800 miles and if it continues to improve I'll be thrilled.

 

On the initial test drive I thought it was a dog but then again, I was driving a diesel everyday too. I have almost 500 miles on mine now and it feels good.

Besides, there's nothing like driving a Jeep. You couldn't wipe the grin off my face if you slapped me with a phone book.

 

I was shocked at how slow the Rubicon was after installing the lift, bumpers, winch, and beadlocked 35" Toyos. This was at 50 miles on the odometer.
Seriously, you had to try to rev it to stay ahead of the neighborhood schoolbusses, but there was little power anywhere in the powerband. And 11.2 mpg was the first measured mileage!
And it wasn't pleasant at all under 2k in any gear, it just didn't seem to want to pull unless you were in 1st or 2cnd. But it didn't seem to like to rev either, leaving you a narrow 2.5-3.9k powerband in which the little V-6 ran acceptably well. Thank goodness for the 6 gears!

Gears, supercharger, or gears and supercharger?

But I read here that it would get better as it broke in.
Now my DD is a Lexus IS350, a highly efficient rocketship of a sports sedan, with a 3.5 liter engine.

Well, with 3800 miles on the 3.8, it's a pretty sweet little engine. It lugs along just great in high gears, even 6th. I even find myself skipping 4th and/or 5th sometimes depending on speed and terrain, and the ability to actually accelerate up mild grades in 5th was unfathomable just 3k miles ago.
Now it does lack horsepower, but has a nice flat torque curve, revs happily past 5k, and if you wind 3rd a bit and then hit 4th hard you'll be going pretty quick coming off that highway entrance ramp.

 

I have an auto w/6k miles and counting...I think the engine is adequate, just dont like the way the auto trans operates even with the OD button off...

I'll try to explain it the best I can....

As I take off from "D" the JK seems to shift thru all the gears, but lets say at a steady speed of 35mph, the RPM drops to 1200 rpm and that's where the engine seems to lag..I either have to downshift to 2nd to keep the speed steady at 35mph or tap on the gas to increase the speed to get the RPM back up so the engine doesnt seem like its hesitating.......

But dont get me wrong, I still love my JK

 

Drives you crazy, doesn't it? Drove me insane.

I regeared to 5.13 from my 3.76. I have 33s. My city mileage WENT UP from 14 to 16. I have to get the diff fluids changed here next week and hope to get some hwy mileage under my belt. Previously my hwy mileage was about 16-17mpg. I think I should at least hit 19 with the way it is running now.

Life is good again

 

I'm am going up a slight incline, nothing long and appears to be an issue. I start at 70 mph and before I know Im slowing traffic and turn off the overdrive and I am pressing the pedal to re-gain the speed. IF I push real hard it screams to 5000-5200 rpm, but I cant maintain the 70 mph nor the 65mph.. I guess I just have to live with it, but I wish I could maintain the 2800-3200 without the overdrive off. Apparently other have the same issues and they have not found resolution.

Is there a chip that will give me that MID-RANGE allowing my Jeep to stay with the flow of traffic? Or are their DYNO adjustments that can be made to assist this?