For anyone who has been unhappy with their AC performance here is a mod I saw over at Diesel Truck Resource Forums.
It involves installing a shutoff valve on the heater core line coming from the engine head.

http://www.dieseltruckresource.com/d...d.php?t=209533

I did this on my 2006 5.9 and it made a huge difference. When engine is hot it cools down so much quicker and my temps out of the drivers side vent are about 10* cooler than before the mod. Materials cost about $15 at Home Depot and took about 10 minutes to do.

 

does anyone know if this mod will work, for a 6.7?? I to am un-happy with the performance of my ac!!

 

Go to post #71 in this thread http://www.dieseltruckresource.com/d...533&page=5

 

Yup be sure and do a bypass so that your turbo gets coolant!

 

So after you put the valve in and shut it off, do you ever need to reopen it or does it stay shut off all the time.

 

I open mine every now and then to allow the coolant to circulate a little.

 

k thanks guys, i'll post somepixs when i get it finished!!!!