2004 Sub 6.0 w/130k.
Bought the truck 2 months ago and sometimes the AC is just cool and other times it will freeze you out. Today (95 degrees), it was blowing cool and the truck felt like it was pulling a 10000 lb trailer as far as power goes. Later today (98 degrees), the AC was freezing and had normal power. Have noticed this before. Can a bad AC clutch cause this extra stress or what?

Things that have been done in the last month:
Serpentine belt & tensioner
AC belt & tensioner
Fan clutch
cleaned fan and radiator

 

Was the difference in cooling when you were in stop and go traffic vs. moving down the highway? I had an 02 Yukon and it did not cool well when stopped at lights or in traffic. The fan did not rotate fast enough to pull enough air through the condenser coils to cool well and no air being pushed through as when moving. I have an 2011 now and the electric fans do a much better job of pulling air and it cools good even when stopped. You might also check the fan clutch to see if it is engaging.

 

it does get warmer at stop lights. Still blows cool but not like what I get when moving. I put in a new fan clutch thinking that was the issue but it has not helped. The Sub just sounds like a school bus now for the first 10 minutes during warm up with all that fan noise. I replaced a 01 Tahoe with this truck and that one never had issues like this. Would freeze you out whether I was moving or not. That truck had manual controls, this one is dual climate.