Sorry guys, didn't really know where to put this one, I was lying awake last night with a nasty cold and cough so no sleep.... This weekend I got my deep fryer out and made a big batch of hot wings and as usual, I get my oil (Canola) up to 350-375*F before dropping my wings in... this got me to thinking why does everyone in the automotive world panic when the oils temps exceed 250*F?? It doesn't seem to phase this cheap canola oil and I know the high quality base oils used in all major suppliers of PCMO's and HDEO's has to better than this cooking oil, right?? Case in point- my 2005 Ford F350 with the 6.0 diesel engine. These are known to have oil cooler issues and folks on the forums as well as OE Ford TB's say oil temps in excess of 250* is BAD!! Why are we so concerned with what seems to be a relatively mild oil temp in cars? Especially if we're running a quality synthetic? Does 250-300* actually hurt todays oils?