I have noticed since the day I bought the truck that when I stop at a redlight once the trucks engine is at operating temp and my AC is on the truck idles fine then it seems to drag down a little bit causing the engine to sound like its under a load. The idle gauge does not seem to move but I can feel and hear the engine sound like its under load for about 5 seconds then goes away. It then comes back 30-40 seconds later. If the trucks AC is turned off it does not do it at all so I am just thinking its the AC compressor pulling the load. Does all trucks do this? Its a 6.7. I was going to ask about it at oil change time but wanted to see if anyone else experienced here?

 

 

I figured so, its just a bit annoying.