i have a 02 suburban 1500 LT autoride. I have a couple problems hoping you guys can help.

First when the truck is idling the ac starts to blow warm but once im moving it starts to blow cold.
also later today i was stuck in traffic for 30 to 45 min the truck started to over heat once i truned off the ac it was back at normal temperature.

So my question is what is casuing this? I came to the assumption that the thermestate is bad. Due to the two symptoms that its showing but what do you guys think?

 

Likely bad fan clutch, you have CLASSIC symptoms.

 

would you recommend GMB product ?

 

I've not used GMB, but see it has good ratings. My 2005 Yukon has electric fans,

 

ill try gmb its a $60 difference

 

I very-rarely use dealer parts; remember, GM does not have a fan clutch factory, a radiator factory, etc.

Look up on Google how to test a fan clutch. Basically, with engine off and still hot, spin the fan by hand, it should not spin too much. Some test with engine on and use a rolled-up newspaper to see if the newspaper shreds (good) or stops the fan blade (bad) when newspaper is held in the fan blades; note that this is dangerous to people though !!!

 

would regular paper work? And ill check that thanks

 

I dont think its that. Hot its stiff but when the engine is warm it does spin. What else could cause this?

 

it did a bit less than 1 turn is it bad? Or could ut be a termostate issue

 

My '01 Suburban was overheating when AC was on at idle. I'd turn off the AC, turn on the heat with the blower on high and the temp gauge needle dropped back to normal. I suspected the need for a coolant system flush which I did with Blue Devil brand flush treatment. I simply followed all directions on the bottle, let it run for 30 minutes, drained it and filled with tap water and let it idle. Even with no antifreeze in the system and with the AC on parked in my driveway, the gauge stayed put at about 185 to 190 degrees. I ran with that for a bit, drained and filled again, ran that a bit, then drained and filled with Dexcool 50/50. It has not overheated since. Oh, I also took off the upper fan shroud and the bezel or whatever it is above the radiator and sprayed out the radiator fins from inside and out. As for that fan clutch, I too had that replaced some years ago. I'ts been so long (I now have 244,000 miles on it) that I can hardly remember why I did it, but I seem to recall a similar situation with the AC working on and off.