Originally Posted By: Sharpshooter69
Maybe this will work.

I had the same problem, no code...I took my 05 Sierra to 3 different shops, the last one a transmission place wanted to tear apart my transfer case to repair some type of actuator end (maybe who knows) gave me a estimate of 600 bucks. I was driving myself crazy couldn't figure out why I would get a different diagnosis at every place. Finally took it to a friend who is a shade tree mechanic....he made a couple phone calls and replaced this very same part. The schematic he gave me which shows the part is TX04-287. On the drawing I believe it is item 38... He gave it to me so I could show all the shops who looked at my truck. Haven't had a problem since...PM me a fax number or e-mail address and I will scan or fax it to you tomorrow. He said it took him out an hour to replace it...