We purchased our 2008 Tribeca in Nov 2011 second hand. Previous owner put 43,000 miles on it. Car was in great shape, sounded great and drove perfect. For the past 9 months we put around 15k on it and progressively had issues. Stumbling/hesitation up hills under load, random misfire codes etc etc. as a shop owner and tuner I dug into it. While I was working on getting the rom defined my wife called me up from an hour away. Car shakes violently, cel is on etc etc. I drove to meet her and scanned it, cyl 5 misfire. Car now had 59925miles on it...just shy of the 60k warranty. Logged the car driving back to my shop watched roughness in cyl 5 go through the roof.. Once back did a comp test and saw 82psi in cyl 5. At this point I decided to bring it to the dealer to see if SOA would warranty it. A few weeks later we get the car back no charge with the following replaced.
2 exhaust valves (cyl 5)
Ring set all pistons
Engine bearing set
Misc gaskets, oil change, coolant etc etc et.
Car is awesome to drive again. Now that we have the rom defined and I can reflash it I have been working on the knock issues it has. No matter the gas used we find knock events under load causing IAM to drop like a rock. Slowly but surely I am working on the timing board to keep this in check and to prevent a future engine failure.