So I just had the a/c fixed on the benz and it wanted to make sure that I was thinking clearly. Before I had the a/c fixed the engine ran at about 90C-100C. I run the MB coolant with water, about 50/50 and a bottle of water wetter. Now keep in mind this is TX and it gets really hot, about 101 today, but now since the a/c is working it is running at 110C. I know that the temp should rise with the use of the a/c but should I be worried? The temp does go back down to 100 if the a/c is turned off, and gets to about 115 when doing approx 70 down I35( I promptly turned off the a/c and slowed down when it hit 115). In town the temp hovers in between 100-110, with the a/c on. I am leaning towards flushing the cooling system and I have made sure that there is nothing interfering the air flow. Is there something that I am missing, or is this just the combo of TX heat and the diesel engine producing the high temps?

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1980 300D European
"The Red Fox"
200,000 miles

2003 Chevrolet Silverado

609 Certification