Thanks for the explanation! I imagine my engine temperature was still above 150F when I restarted the car and the rpm’s went to 5k. Lesson learned and hopefully I’ll forget all about it by the time my 4Runner hits 200k milesIt's not just about oil film it's also about operating temperature and the tight clearances at those temperatures. A cold engine is looser, and an ice cold engine might hit oil pump bypass above 4k RPM, extreme cold with very thick oil (like a 15w-40 or 20w-50) could also result in the oil pump drive breaking off. Most antiwear additives also don't work below 150°F, especially zddp. Even in the extreme cold we've been having up north it takes several hours of the engine being off for the coolant temperature gauge to drop to the bottom, and 8 hours for it to completely drop to ambient temperature.