Do a search on the forum here, someone did this about 6mo or a year ago and I think they even had some pictures. Also, your dealer is way out to lunch. $4500 I'd believe for a transmission, not a xfr case. My transfer case was replaced under warranty at 45K miles due to the 98-99 year problem with the truck shuddering on tight turns due to the xfr case binding. Cost was amazingly (to me anyway) only $1300 ($1000 for the case and $300 labor (about 3hr job)).

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