I replaced the ac on my 02 suburban with rear ac this weekend. I replaced the compressor, condenser, accumulator dryer, and oriface tube. Flushed the lines under the hood, vacuumed and recharged the system. Heres where im not sure if im just paranoid or not. I can get in the truck with the vent temp at 110 starrt the truck and by yth time i leave the parking lot the air charge is down to 80 another 5 min its down to 60 and another 15 it will get to 40. My question is, whats normal for how fast its suppose to cool off? I know humidity is a big factor, i live in the Louisville KY area where humidity is high when its hot. I just feel like it should cool down faster to at least 60°f. I wound up at an estimated 48-50 oz of freon to get the pressure up past 30psi low. When i was done i had it up to 35 low and 175 high. I may check again to double check.