I bought a 6.4 about 2 months ago and I've been noticing recently high oil temp. It started out just above average but now it's up to 235-245 oil temps with 198-206 coolant temps(interstate) I origanlly thought there was one solution, replace the oil cooler... But after reading another article there is possibility for an airlock in the system causing high oil temps? It would make a lot of sense, my radiator is leaking I have mishimoto radiator that started leaking 3-4 weeks ago I've filled it one time (one gallon wasn't quite enough to fill it) and they didn't seem to improve at all, then I read there's a certain tool to preasurize it that I know I didn't use and now maybe I have a airlock somewhere? I drove it to Dallas and back which was 6 hours and on the way there I was pretty much between 220-230 on way back it was 235-245 so do I just need to flush the coolant system then have it refilled or replace the oil cooler or where do I start?