Temps getting high while at idle

[Ataylorlv]

2005 yukon xl 2500 6.0. As stated, my temps are hitting around 230 and the ac gets warm when idling for a more than a couple minutes like in a drive thru. Just replaced the thermostat, fan clutch is less than a year old and appears to be in working order. I am wondering if I have an airflow issue. I tow a 5500lb travel trailer, so I upgraded the trans cooler to a larger one and I replaced the stock radiator last year and went with a nice 2" thick aluminum one instead of the 1" core that was from the factory. Do you think that the added trans cooler and the thicker could inhibit proper airflow? I can shine a flashlight through all 3 (condenser, trans cooler and radiator). Thanks for any input. Oh yeah, I live in Vegas where it can be 115-120 on the street. 

[carkhz316]

Have you verified the engine temp via live data? The gauge could be reading erroneously, as often can happen with the stepper motors in the cluster. The whole point of bigger coolers and radiators is to have better cooling, so that's not bound to be any issue there.

[Ataylorlv]

The gauge is accurate. Checked live data. Might be time to ditch the mechanical fan and get a good electric fan setup. 

[carkhz316]

I would keep the mechanical fan, as they will move more air more efficiently then a electric one for that truck. I just re-read your first post, and even though you said the fan clutch is only a year old, the fact that you are having overheating issues AND poor AC performance while idling or moving slow tells me that the fan isn't moving enough air (clutch isn't working properly). I would check it out by letting the truck cool off and giving the fan a spin (engine off) and verifying that it doesn't spin more than a revolution or two. If it free wheels, then the clutch is bad. I hope this helps, and good luck!

[Grumpy Bear]

Different radiator. Did you retain the fan shroud? 

[Ataylorlv]

Same fan shroud. Fan clutch solid, it only spins about 1/4 turn when I spin it by hand. Could be worth a warranty replacement just in case. Replaced thermostat last night, seems to hold closer to normal Temps, but the a/c still blows barely cool when sitting in one spot. 

[txab]

Which clutch did you purchase? They make a "heavy duty" and a "severe duty" in the aftermarket. On your AC, you may be slightly undercharged, but I'd make sure everything else is correct before going down that road

[Ataylorlv]

I bought the severe duty from O'Reilly. Maybe I should go with the oem one. I'll check the ac as well, but it should be good. I replaced everything 2 years ago when the compressor went out. Thanks

[txab]

What's your idle RPM?

[Ataylorlv]

It is between about 545 rpm