I have a 2012 JK Unlimited Rubicon to test this week.
Equipped with the 3.6 liter VVT V6 and W5A580 5-speed automatic overdrive transmission, the 2012 is a new breed of cat. So far, I've only driven it on the pavement, but it's on-road performance is stunningly better than the 2007-2011 Wranglers.
There are some obstacles for the aftermarket to overcome, such as sensors that are so sensitive the Jeep goes into limp mode if the gears (ring and pinion) are changed, a vacuum pump mounted behind the front bumper, and the driver's side exhaust loop.
This loaner is a press fleet Wrangler, so has seen thousands of hard, tough off-road miles. It's been thrashed. The gas tank skid is bashed up into the tank and every crossmember and control arm is scraped thin on the bottom. The exhast from the midship muffler to the rear is brand new, meaning it was so thrashed it had to be replaced. The only parts of the exhaust that aren't new are the manifolds and down pipes, including the driver's side loop. Maybe it isn't as much in harm's way as we thought?
As many of you know, I was underwhelmed with the 3.6 when I first drove it. I don't know if that pre-production 2012 was different, or there was somthing else wrong with it, but it didn't run like this Wrangler does. I'm especially interested in the new Rubicon's crawling performance. The 3.59 first gear in the 5-speed automatic tranny should help tremendously there.