Volfy
Some fava beans and a nice Chianti
- Joined
- Dec 5, 2010
- Messages
- 1,496
- Reaction score
- 1,372
- Points
- 113
- Location
- Gulf Coast
- Genesis Model Year
- 2021
- Genesis Model Type
- Genesis G70
Correct. The reason for this inextricably leads to a conclusion that is rather counter-intuitive. Let me explain:0w weight oil produces less friction in cold weather than 5w, and can offer better fleet MPG averages, keeping the government environmentalist happy. I think they'll choose it for that reason over engine longevity.
All other factors being equal, a 5w30 oil will actually warm up faster than a 0w30, albeit by a very small margin. This is because in a thin film lubrication system, what produces frictional heat is not metal to metal contact. If that actually happens, the bearings will self-destruct in very short order. Instead, what occurs is the shearing of the thin layer of oil film, which produces frictional heat. The higher that oil's viscosity, the more work has to be done to shear the higher-VI oil, resulting in more frictional heat being produced. This is how 0w30 has a higher fuel efficiency than 5w30.
So, ironically, If your goal is to protect the engine from prolonged cold start running, you would naturally want that engine to heat up as quickly as possible in very cold temps. A slightly higher viscosity index (VI) oil actual helps. That is, as long as the oil's pour point characteristics allows the oil to flow quickly to coat the bearing surfaces where effective thin film lubrication can occur as soon as possible.