2007 International 9400i A/C problem

thanks heavy, I just had it in the shop a couple of weeks and they couldn't find anything. It happened again where I pulled into a shipper without the AC running and by the time I got into a parking spot, the temp was up to 205. I turned the AC on and it dropped to 180 almost instantly (30 secs). I can hear the fan kicking on and off with the AC on. Beginning to wonder if the Radiator fins are stopped up and its not getting enough air flow. I've also noticed that the oil temp is up a little as well running around 240 or so. When I asked the guys at cummins they checked the oil cooler, oil cooler thermostat and flow and they said everything is fine with the oil, the ecm is reading the oil in motor at 230, and they gauge on the dash is reading the oil in the pan. The org radiator is still in the truck and I had the TA use an air hose to blow it out last year but not too sure the tech did it enough to get it clean

I've had the coolant thermostat checked, the coolant system flushed and pressure tested, everything is good. Has brand new coolant and all levels are good.