PLEASE HELP....Had the transmission replaced in my 2009 cadillac escalade 6.2 by cottmans trasmission.The day i picked it up,the tranny went out that night.They ordered another one and 2 weeks after,i started having other issues.The other day i went to work on a customers car.Turned my truck off and when i went to start it,it was shaking like crazy.Says random misfire and nothing more.Cottmans towed it back to them and said to change my plugs and wires.Did that and its doing the same thing.Before they worked on my truck,i didnt have these issues.and now,they declined to do any further work to my truck.Any ideas on why its still a random misfire