1993 Blazer K-1500 slipped out of 4H going up mountain pass
 

Speedomoter quit working. Engine over-revs now (feels like transmission is slipping a little).

I could not stop right away as I was part of the way up a two-lane mountain pass in icy/blizzard conditions. Got the transmission back into 2H.

I am getting codes 13, 24, 32, 43 & 72.

Did something bad mess up. Transmission was acting funny before I bought it and the previous owner had some computer issue resolved which seemed to fix the problem. Any help will be appreciated.