I am getting a grinding noise from the front of my truck when it is in reverse. Not a constant noise, it goes in and out. Sounds like a grinding gear noise. Dealer has already changed transfer case, but it was not the fix. Has anyone else had this?? Also, the engine went into fail safe mode yesterday for @ 30 min and then went off. i don't think the safe mode is related to the grinding noise. Man I wish I had went with the 250 6.0 deisel fx4. This thing is a piece of ----. THANKS!!!!!!!!