The W that is between the numbers stands for winter. The number after the W represents the viscosity of the motor oil at high temperatures. The higher the number, the thicker the oil will be. 5w-40 Vs 15w-40: Key Things In Common Multigrade oil. The 5w-40 and 15w-40 are both multigrade oil.
In Brad’s case, his 15W-50 racing oil may be too thick to flow quickly enough to fill the spaces between the crank journals and main bearings while the engine is running. The oil won’t form a consistent lubricating film, allowing metal-to-metal contact and wear. His engine was designed specifically to use a lower-viscosity oil, in this case
10W - 40 oil is a little thinner than oil with a grade of say 15W - 50 or 20W - 40/50. In the Philippines it is better to use thicker oil like the 20W - 40/50 because it is hot and you do not need thinner oil that would lubricate at low temperatures. However, this is not the end of the story. We have oils now that are synthetic and mineral based.
Valvoline Premium Blue One Solution SAE 15W-40 Diesel Engine Oil 1 GA. Related Questions and Answers Which is better 10W30 or 15W40? 10W-30 oil’s film strength may be lower and it may be more susceptible to oxidation than 15W-40 oil. As a result, superior additives are required to make a 10W-30 engine oil as effective and long-lasting as a
A decent race oil will take about 10 hours of hard track use and a semi-syntehtic or hydrocracked base stock will last about an hour before the oil begins to lose viscosity. Are 5w and 0w oils too thin? I read on many forums about 0w and 5w oils being too thin. 0w-40, 5w-40, 10w-40 and 15w-40 are all the same thickness (14 centistokes) at 100degC.
Iowa. Aug 7, 2020. #3. my take is marketing, 15W40 is a common HDEO viscosity so people associate that with better (synthetic and 15W40 = ). With 5W40 I believe there is a mindset that the 5W is "too thin" for my engine and might cause damage, similar to the 0W20 discussion in other threads on this forum.
The Final Verdict on 5w30 vs 10w30 for High Mileage. Both high mileage 5w30 and 10w30 engine oils have the same additives, the only difference is the viscosity at cold startups. Since both oils have the same operating temperature viscosity (30) and additives, they will perform exactly the same. However, 5w30 flows much better than 10w30 during