I'm coming up on 70K on my 2011, with 2.5 inch lift, OME shocks / coils, AEV drop brackets, and 265 75 16 Cooper ST's. Just replaced the starter motor at around 65K after the pinion gear wasn't retracting quickly enough on cold starts and was hitting the flywheel. Upgraded all the bolts where needed to the shouldered kind to avoid wallowing out the bushings and added a few moog joints to improve the steering.
Other than that I have just kept up on regular maintenance - nothing special, oil and diff changes, brake pads, air cleaner, and a religious dedication to checking the oil level. Also installed a Mishimoto auxiliary trans cooler for piece of mind when off-roading.
The 3.8 is such a simple engine with quite a few well thought out parts that I hope to keep it going for as long as possible.
Almost forgot, just installed a sprint booster - all I can say is " wow " what a huge difference over stock, it basically removes all the lag from the gas pedal and really sharpens up the shift points.