GMC Troubleshooting Questions? Ask a Mechanic for Answers
good morning my name is ***** ***** I will assist
you did nothing wrong with adding def. it is only the tank. the ecm controls the amount used in a re gen.
the smoking may be a leak of some sort either from oil or coolant. have them check this and be sure it is resolved before accepting the truck back. did you take out an extended warranty??? t is odd that this all happened this soon after buying the truck.
how are you making out????