Zorro,
I have an '02 with the 3.7. I have a '94 3023, and it does slow the jeep a bit going up hills (Rockies). I live at around 6000 feet, and towing up here is different, I noticed that with my pop up trailer from MO and KS to CO.
I have not however, towed the trailer up and over the rockies yet, I know it will be real slow, as with the old pop up, (2500lb), I was only able to maintain 45mph over the peak at Eisenhower tunnel on I-70, so I expect to only be at 30 with the TM.
As these guys have said, you will need a weight distribution hitch. You can drive it without, but it would be safer IMO than to not have a WDH. I have hauled the TM about 200 miles total already (had nowhere to park it, so I got to take it b&f to work for a couple weeks
) I noticed no sway going up to 70 mph, so I would say a WDH alone would do you fine.
I plan to install a Tranny Temp gauge in mine as I do not trust the idiot light. The engine temp light has not even budged from just below the half way point as it did when I was not towing, and my tranny fluid does not seem hotter after driving than it did prior, nor have I seen any change in shifting, just be sure to keep OD off.
With your '06 and the 42RLE Tranny, you should keep it slow though, as when you go up steep grades (if you visit the Rockies or Appalachians) your tranny temp light will come on (that is without towing anything, just a quirk of the 42 tranny) I have a different tranny since my KJ was built in may of '01. If you want to ask anymore questions about towing with the Liberty, feel free to PM me or visit our forum at
www.lostkjs.com A lot of good questions on your vehicle there. I know some others tow with their newer KJs as well.