After my A/C was blowing hot and the rear evaporator recently found to be the slow-leaking culprit, the system was topped off by a shop with refrigerant, oil, and stop-leak. My hope is that the leak is slow enough that I can keep it functional each summer with occasional refills, and without replacing the entire system or removing the rear function (separate thread on that here). I just got back from a 500+ mile trip in the Suburban, towing my 9500# RV trailer. The engine was working hard, but I watched the temp closely to make sure it remained under control. Outside temperatures were 80's and low 90's so I was running the A/C. It was always cold, but sometimes the front air vents barely blew with any force, like a whisper. I could turn up the blower speed and the motor responded as expected, but airflow wouldn't increase. Then other times the system would suddenly be blowing fine. I couldn't tie the issue to anything I was doing with the driving or engine temp, if that affects A/C performance. I tried all sorts of things -- changing Upper/Lower airflow modes back and forth, fan speed, system turned off then back on... but could never seem to cause the low airflow OR fix it myself on the fly. It was very inconsistent. Does this sound like a RECIRC issue when on Max A/C? Blend doors malfunctioning? Sometime else? Or is this just typical with 95 or older trucks? FWIW I recently replaced the blower motor and cleaned the front evaporator, and the motor sounds/responds just like it should.