There are a lot of "fuel diluters" out there. Mainly direct injection/ turbo charged engines. It's nothing new. Maybe not as bad as the 1.5T. I have seen UOA on this forums of people with the 1.5T using 0W20 and change there oil before or at 5k and no huge degradation. There are people out there that haven't even have had problems with their 1.5T. At the end of the day, I always believe you do you and do what helps you sleep at night. If people feel 5W30 is better for their engine. Go for it! Not hating at all. IMO one of the best thing to do with "fuel diluters" is change your oil more often using the recommended fill. Not to be mean or an a$$ but if we are talking logic, the best logical solution is get rid of the car if you are having huge fuel dilution issues. Like you said. It can't be a good thing regardless of what grade oil you use.
Originally Posted by Danh
The OP's issue is with fuel dilution and the Honda 1.5T is a serial offender. UOAs here regularly show a 0w-20 diluting from an 8.xx cSt @ 100C to 6.xx. It seems reasonable to assume the HTHS would also suffer degradation from the 2.6 minimum to something in the low 2s, too. Is this harmful to engine? Who knows, but it can't be a good thing. So while there's nothing inherently wrong with an 0w-20 and there are tons of high mileage examples out there, applying this logic to fuel diluters may not be appropriate. Now that my diluting Honda CRV is past warranty I've moved on to a light 5w-30: it'll become a 20-weight soon enough.
Originally Posted by Eddddd
IMO. 0W20 oils do not necessarily cause more engine wear and switching to a xW30 will not necessarily protect your engine better for a vehicle that is spec'd for 0W20. Now I'll probably get attacked by forum members and wanna be engineers about how xW30 oil is better and xW30 oil's HTHS, MOFT numbers, CAFE, engine spec'd differently in other countries, etc. While it does matters somewhat, again it doesn't mean 0W20 is a bad oil grade and it is not protecting your engine properly or that x30 will protect better. In some instances but not all, going to a higher grade may cause more wear. Especially with VVT. The oil won't form a consistent lubricating film, allowing metal-to-metal contact and wear. If an engine was designed specifically to use a lower-viscosity 0W-20, its lower viscosity allows it to flow faster and fill the tiny clearances between parts, leading to a durable, consistent lubricating film. Yes I know there are engines in the US that are overseas and is spec'd differently in other countries but who's to say the ECM is not programmed differently or they use a that different VCT (cam phaser) calibrated to that weight of oil? In the beginning W20 was primarily for CAFE regulations but it's been almost or over 20 years since then. To say it is strictly CAFE related nowadays is not entirely true. Most likely going to a x30W for an engine spec'd for a 0W20 oil will not harm anything but the argument that a x30 oil will protect better, I don't buy it. I have used 0W20 oil on my cars that are spec'd for 0W20 and conducted oil analysis with no issues. 0W20 is a robust and synthetic oil that will protect your engine. At the end of the day do you and do the research. You will see many on this forum that will tell you 0W20 is great oil and vehicles with 200,000+ miles on their car using 0W20.
Originally Posted by aquariuscsm
Is this a 0W20 spec engine? It's looking like more and more people are running a W30 in W20 spec engines, me included. Makes me wonder if in fact a W30 oil is better at protecting an engine from wear than a W20.