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Which engine oil having high level of resist to fuel dilution
- Thread starter MetalSlug
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Mostly a higher grade.
I take it you changed your mind on posting the thread but I'm having lunch and I'm bored. Not only do oils with a higher viscosity resist fuel dilution but also lower vii ones but the specific polymer matters. I believe star polymers do better but having less polymers is still preferred. But if the oil will have to suffer alcohol like e85 then there are alcohol oils and hpl and others sell them.
I imagine it's for your lexus NX. Something like ST 5/10w-30 would be great. If mag 1's full synthetic SP pcmo oils are identical to supertechs which I think they are then you'd be better off with the 10w-30 which is 5.2% noack and 150 vii while the 5w-30 is 12% noack and 170 vii and change frequently like 3-4k.
I imagine it's for your lexus NX. Something like ST 5/10w-30 would be great. If mag 1's full synthetic SP pcmo oils are identical to supertechs which I think they are then you'd be better off with the 10w-30 which is 5.2% noack and 150 vii while the 5w-30 is 12% noack and 170 vii and change frequently like 3-4k.
The question has been asked many times and the general consensus seems to be there is no such oil, but you can use a thick-for-grade euro oil or step up one SAE viscosity grade to compensate to some degree for the thinning effect the fuel will have when mixed into the oil. What that doesn't do is also compensate for the negative chemical interactions between what's in the fuel and what's in the oil, which is why extended oil change intervals much beyond 5000 miles are usually not recommended in engines that regularly suffer from dilution over, say, 2-3%.
The follow up question is usually "didn't the OEM account for dilution when they specified (recommended) the oil grade?"; we know from public records that OEM's must specifiy thinner oils to avoid government fines. Theoretically the OEM probably did engineer the engine to operate with dilution and thinner, ILSAC type oils. However it was likely done as a caluclated compromise to some amount of engine durability/longevity. Whether that compromise has a tangible impact on the vehicle's (not just the engine's) longevity seems to be up for debate. Furthermore, as seen with the recent 6.2L GM issues, unless manufacturing quality control is tight, what might've been a minor issue can be magnified and exacerbated when running on the bleeding edge of minimum frictional losses (thinner oils).
The follow up question is usually "didn't the OEM account for dilution when they specified (recommended) the oil grade?"; we know from public records that OEM's must specifiy thinner oils to avoid government fines. Theoretically the OEM probably did engineer the engine to operate with dilution and thinner, ILSAC type oils. However it was likely done as a caluclated compromise to some amount of engine durability/longevity. Whether that compromise has a tangible impact on the vehicle's (not just the engine's) longevity seems to be up for debate. Furthermore, as seen with the recent 6.2L GM issues, unless manufacturing quality control is tight, what might've been a minor issue can be magnified and exacerbated when running on the bleeding edge of minimum frictional losses (thinner oils).
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Yes sir
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Higher viscosity is not the solution because I cannot believe that viscosity loss is the only harm that fuel does
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You have no choice, what are you going to buy?
An oil with the least numerical range in viscosity rating. IE 10W-30 trumps 5W-30
So 0w8 then?
Well an argument could be made for that in a system designed to use 4 cSt oil. Which are no engines out there.So 0w8 then?
Is there any logic in moving up a grade? Fuel dilution occurs when fuel gets past the rings, so if there is thicker oil in the ring lands, can that slow the passing of oil into the crankcase?
It can help but I argue going 0W-40 is no cure because it becomes sae 30 pretty quickly. Just go 10W-30
This.@Zee09 may be illegal in 6 states, he may have the death sentence on 12 systems (Star Wars reference), but he speaks the truth!
Short trip, short OCI.
If it's loaded with fuel, it doesn't matter what brand/viscosity it is.
This is why I'm a believer in 5k or 6 months, whichever comes first. Hasn't failed me yet.
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5k lol. I am at 3.5% fuel at 4,500 miles and 4 weeks, and I am far from a short tripper. If I was a short tripper I would do 2000 miles or 2 months max.
@Zee09 may be illegal in 6 states, he may have the death sentence on 12 systems (Star Wars reference), but he speaks the truth!
Short trip, short OCI.
If it's loaded with fuel, it doesn't matter what brand/viscosity it is.
This is why I'm a believer in 5k or 6 months, whichever comes first. Hasn't failed me yet.
- Joined
- Oct 25, 2021
- Messages
- 2,207
Orly nao
0W-8 engine oil is primarily used in certain hybrid models from Toyota and Mazda, particularly those prioritizing fuel efficiency and low emissions. Examples include the Toyota Corolla Hybrid, Toyota Crown with 2.5-liter Hybrid engine, Grand Highlander Hybrid, and the Mazda 2 Hybrid (sold in overseas markets).
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