I just had everything replaced except the lines for AC. The AC shop says they put in 3 lbs. But the vent temp takes a long time to cool to 70 or less if I am lucky at 95 degrees outside. It's a 100 right now outside in Vegas and vent temp not going below 75. We even replaced fan clutch and water pump. The rear unit takes too long to cool down as well. The receiver does not sweat. When the temp is around 85 in the morning the vent temp is a 57 degrees. So I can drive into town to shop and come back to get into 130 degrees inside and it will take 15 or so minutes driving before vent temp gets to around 75. So the inside is more like 90 and moist. If the Tahoe has frt/bk AC units, is the receiver bigger? The receiver that was put in by company looks smaller than original to me and it doesn't sweat. Is that a heat switch on the side of receiver? I've spent thousands to replace frt and bk units. Something is not right. I'm going to pickup gauges to read temps today. What pressure might I find for low and high at 110 degrees outside? Does this 2002 Tahoe use more than 3 lbs of freon? What could be the problem? They extracted and refilled twice. Last update: Replaced accumulator with one for frt and rear AC I got from Chevrolet. Couldn't find the correct unit at 3 Nationwide parts stores. They were all selling a short size unit and that is what was installed by a AC shop last year. Go figure. A long story short. Pressure is good. 107 degrees outside and going down freeway and vent temp 45 degrees. In traffic stop and go, vent temp is moving under 60. Might need another vacuum too make sure all the air was removed. Maybe new fan blades or helper fans in front.