I have an 09 2500 duramax and I'm having some issues. I was driving it*a few days ago and the service engine light as well as the service stabilitrak light came on. The the line under the gear display also disappeared and it appeared to be stuck in 3rd and was rough when putting it into reverse. I could turn it off and let it sit a while and the codes would be gone but would come back after the truck got warm.*Had a buddy come out and ran the codes and I can't remember the code number but it was for the shift selector switch. I changed the nsbu and drove it a few miles. After it warmed up the service engine light and service stabilitrak light came back on and the symptoms returned. I really don't want to start throwing parts at it. Any ideas on what to check next or what it could be? The is for all the help.