Ac heating my lifted truck slowly> help please
 

Yes, The truck checks out fine cooling system wise at dealer. Has a 3 inch body lift I think, AC runs the temp up close to redline. Dealer said the prob is becasue shroud is cut at bottom, and AC heats up in hot traffic cause condensor pulls it hot air. Mechanical fan is stock. I was told electric Fan is what I need. Thermostat, and Coolant temp sensor just changed, but a waste of money.

2001 Chevrolet 1500 v8 ex cab automatic 4x4 . Knock sensor code is there also. We are at 100 degrees all day in texas now.