Transmission Slip? 2005 Chevy

I left for work yesterday am, I thought I may be slipping on the icy road. So I locked in 4x4. I was still noticing a slight slip. As the rpms would rise with out an increase in speed. On the way home it was maginfied 100x worse, to the point the truck would hardly drive.This is the first time I have had this problem, with this vehicle. Its a 2005 chevy Silverado with 65k miles. I dont tow anything other than a snowmobile trl. and sled. Can it just be a fluid and screen change? Or is it possible to have blown the transmission? The truck is going to the dealer Monday am. Thanks for any input.

They will most likely need to disassemble the trans to fix it. So, might as well rebuild it while there. The slipping has already damaged the clutches, and they should be replaced.

Why are you taking it to a dealer unless it’s still under warranty? If they recommend a transmission overhaul, get their estimate as well as second and possibly third opinions from reputable transmission shops in your area. Check here: http://www.cartalk.com/content/mechx/ for one near you.

Thank You