My oil temp is at around 220 while crusing and 240ish when driving hard. Would this be ok, til the next oil change? I have mobile1 synthetic wannabe and will be going back to good stuff after I burn this (just changed it). I'm considering something thick, like 10-50, 20-50. Input please. I used valvoline, prior and it sits at 200 cruising and 220 hard driving.

 

I often see my oil temp in that range when boosting hard. I wouldn't be worried.

 

I think that you should stick with what works...I also use valvoline but in a 10-30 grade I live in FL 200/220 in normal...