I had taken the Jeep to the dealer to have the speedo calibrated for my new sized tires. Well, they suck so the speedo was still off (see pic# 1). So, I bit the bullet and baught the calibrator offered by Hypertech (see pic# 2). This thing does wheel sizes in .25" increments up to 55". It will also do different rear gear calibrations if you had swapped out your gears (I didn't so I left this setting stock. My tires are 31.57", so I set the setting to 31.50" and it is fairly close now (see pic# 3). I took a short highway trip to see if this had cured my "hunting" issues while in cruise control and it seemed to do a lot better. It only downshifted once going over an overpass vs. before it used to downshift about two gears to ramp up to speed. I will have to do a longer ride to get a better feel for it before I call it "fixed". The Hypertech unit ran me around $130 shipped and it only took me 10 minutes to program. Also, this unit is internet upgradeable to a HP/TQ programmer if they ever make a program for the '06 3.7L.
PIC# 1
PIC# 2
PIC# 3
PS: On the 3erd pic, the angle of the camera makes it look like I'm doing 50mph. In reality, the needle was just under 50mph (probably 48/49mph).
Sorry for the cell pics...