5w50-ouch

[merlinmol]

Originally Posted by El_Tortuga Keeping the engine bone stock to maintain full warranty. It will get tracked, and this is Texas so better to pay the piper now than risk any oil / heat issue at the track. As an engineer myself, I'd be fairly certain a cost conscious company like Ford wouldn't call out such a high spec oil unless they truly saw the need. If it is only truly required for certain scenarios then so be it. So we know that the ECU will dial back the engine if oil temp gets too high. What I don't know is if they move set point up in the track pack calibration to take advantage of the better heat resistance of the heavier full synthetic. I have been told that the regular GT (non BOSS) guys tend to run into heat limits at the track. Paid good coin and special ordered to get the track pack, won't cheap out now.

I can't blame you there, however, mine is modified. I need a better oil for racing, RP HPS is for modified street/race, and XPR is race, I don't race enough to justify the cost of running XPR all the time. However, those oils all have performance additives which will typically void warranty. Pretty sure I did that adding a supercharger and a custom tune....