What is a safe Engine temp for today's oil?

[el Rojo]

The thread about transmission temp got me to thinking about engine temp.

I'm driving a 2015 Chevy Duramax with Mobil Delvac oil (standard oil for Chevy dealers) in it. The hottest I've seen my engine temp is 225 degrees going up Wolf Creek Pass in Southern Colorado. It's normal temp is around 208 and it red lines at 260.

When does Mobil Delvac start breaking down?

Red

[tyates007]

I can’t speak to when your Mobil will breakdown but 260 is pretty standard getting too hot. Normal oil temp would be 15-20 degrees more than your coolant temp. So based on what you posted above you are right in line with that.