Sorry I havnt posted outcome of my issue for my blazer....this is whats been goin on.....when it rains it shifts just fine...my 4wd light switch lights up can hear tccm clickin when I push the buttons so its
Still good...when it dries up outside its back to normal....lol...so just for ****s and giggles I started pullin
Fuses and checkin them replaced some of them..then low and behold my shift problem went away
So I thought...now I know its electrical...ill post what I find

 

Ok.. . I feel like a complete moron........ When i bought my blazer it had an after market alarm installed by a different moron.......just behind the coolant overflow tank is what im assuming is the ecm,.. well they had the alarm tapped into the wires one in particular..... So when i took the alarm out i used a butt connector... Not knowing what this wire was for.... So this last weekend i pulled out my soldering iron cut the butt connector off and soldered the wire together covered it with heat shrink wrap and low and behold shift problem gone!!!!!!..... Woo hoo!!!!! .... ....... Thank you to all who have replied.....

 

Nice! Thanks for the update.

 

New up date.....I found out after about a week of shifting fine,the problem came back..so on a hunch I pulled the power connectors on tccm , this was a month ago. It's been shifting and running fine. My belief is its the encoder motor that's bad. I've spoken to two separate mechanics, one I trust and one kinda iffy....on running my blazer with tccm unplugged....I mean I don't plan on taking it off road anytime soon.....one more thing these 4.3's do not like cheap knock off caps and rotors AC delco or Delphi work the best....fought that issue for a couple weeks...ugh.....thanks...