Elevated oil temperatures and bearing failure

[kosl]

At what temperature would oil (10w30) have to reach to cause extremely premature bearing failure? Links to any articles pertaining to this would be very much appreciated.

[MagicRat]

Originally Posted by kosl

extremely premature bearing failure?

For this "extremely premature" failure, all the oil, including the oil in the pan would have to be essentially on fire, or cabonizing, as it turns from a liquid into ash. This would require oil temp of at least 450 deg. F, for all the oil, including that in the pan.
This would produce so much engine smoke, from the fire, boiling coolant etc, it would be hard to miss when driving the car.

Usually overheated oil does not cause such an extreme catastrophic failure. Usually it produces oil 'sludge' or thich deposits over many thousands of miles that eventually blocks oil lines and passages, which causes engine (and bearing) failure due to oil starvation.

[UncleBob]

excessive heat over time can cause the oil to break down quickly. Air cooled engines would see over 300* F at times and it was recommended to do more frequent oil changes because of it. Otherwise it loses its viscosity and shere properties

most water cooled engines rarely get over 250* F. 180*F is considered a minimum to keep condensation out of the oil