 Vehicle worked flawlessly till 7500 miles.  At that time there was loud knock and vibration from trans area.  Since then there is intermittent vibrations and shudders.  Dealer 1st stated they can find nothing, then, this is normal.  If normal, I think it should happen all the time.  Dealer then stated it sounds like torque converter, but won't fix.  Told factory rep would contact, but never did.  Am afraid vehicle will let me sit.  Would consider trading, but was told value is zip due to vehicle transmission reputation. Would love Nissan to step up to the plate ands repair / replace.  Anyone listening?Wow, what a piece of crap, and Nissan service at manufacturer level is no better.  After 3 months of run a round, the dealer told me to please find another dealer.  There is nothing wrong with the vehicle and they are tired of looking at me.  So, took vehicle to dealer 50 miles away.  They immediately recognized the problem, but, listen to this, were not able to make immediate repairs.  They had to call Nissan for authorization.  First Nissan told dealer to change tires and wheels with another vehicle, hoping that issue was tires/wheels.  Well, that didn't work, so Nissan told dealer to replace torque converter.  Done, now the problem was worse,  Finally, dealer told to replace transmission.  Finally, problem solved.  Problem was, I was traveling and need substitute transportation.  Nissan did pay part of rental.  Due to substandard treatment by Nissan, I traded to vehicle for new Toyota Highlander limited in 1/15.  That vehicle now has 25,000 miles and performs flawlessly.Lets review, bought Nissan in 7/14 with sticker of 44,500, Paid 38,500. Problems started in 10/14 and finally resolved in 1/15 by final repair and trading for Toyota.  Nissan value is terrible.  Nissan dealer offered 20,500 (less than 50% of original sticker) to trade vehicle for new / improved Pathfinder.  Sorry, burn me once, shame on you. Burn me twice, shame on me.  I work too hard for my money to waste it on "pretty" junk.