As in it’s a secondary yard truck for local hauling and boat transport to/from launch.
As long as it’s got enough hp to pull my 24’ boat out of the water it don’t matter.....and seeing as I just pulled a 30’ Grady White out last week that my buddies Chevy could not it’s all good under the hood
In all fairness his was a a half ton with highway gears, my dodge is a 3/4 ton HD (1 ton pkg) with 4.10 gears.
The range is relevant to starting cranking speed (and battery performance) a whole lot.
The way to read it is, "never thicker than 5 when cold and never thinner than 30 when hot". But the actual preferred SAEs is a matter of many details of interior engine design and that is a call only the manufacturer can make.
Funny, the ideal is constant viscosity, that is, the widest possible range.
lousy musician in post 21 said about all that can be said on this thread.
B.
What I find interesting is that the cars sold in North America (US) specify 0W-xx oils, while in other countries the same cars will have 5W-xx called out.
This to me shows that the oil is a federally mandated thing and not strictly that of the manufacturer.
With that, I tend to oil equipment per the conditions and how I see fit after years of rebuilding and modifying engines.
Now if you really want to discuss snake oil, there is a product that I have used, off and on, for over twenty five years that has touted claims of 3% power increases in internal combustion engines.
This to me shows that the oil is a federally mandated thing and not strictly that of the manufacturer.
With that, I tend to oil equipment per the conditions and how I see fit after years of rebuilding and modifying engines.
Now if you really want to discuss snake oil, there is a product that I have used, off and on, for over twenty five years that has touted claims of 3% power increases in internal combustion engines.
Not sure about that, seems main reasons cars jumped to 0w30 is FAP exhausts and harder norms of gazoline cunsumption and CO2 reduction targetts. EU seems to lead here, maybe Japan as well.
Since ECO3 norms in EU I beleve cars are 0w30 since 2010 maybe and go soon to 0w20.
Fluider gives less friction hence reduction of emissions and cunsumption, dunno if better for the whole engine agging but a member also said what matters the most for engine long life is mainly additives.
Since ECO3 norms in EU I beleve cars are 0w30 since 2010 maybe and go soon to 0w20.
Fluider gives less friction hence reduction of emissions and cunsumption, dunno if better for the whole engine agging but a member also said what matters the most for engine long life is mainly additives.
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View attachment Safari - Jul 9, 2019 at 11:00 AM.pdf
Article on the use of thinner oils and the reasoning behind the shift
Regards
David
Article on the use of thinner oils and the reasoning behind the shift
Regards
David
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Yes, easy to see the benefits of slicker/thinner oil (including reduced effort to pump it around the engine... BTW, that's a lot of fast pumping and helps with cooling on some vehicles).
Odd to read about retro-spec'ing engines. Doesn't the oil that is spec has to work together with ring design, oil passages, turbos, etc?
But what are the downsides of thinner oil? Piston ring wear? Seepage past the rings and ring gaps when running and when off?
B.
Internal engine clearances really haven’t changed in 50 years. Engine controls sure have though.
That can be a big surprise to put thin oil in a worn out engine, have had some of those that would smoke with cheap 10-40, yet perfect with 20-50.
As for the wear that one may suspect from a lower viscosity oil, that can be helped with better additives.
I would be concerned that more average quality oils would have additives that would not hold up as well in either the lower viscosity or with a huge split in viscosity rating. Maybe technology has helped here and allowed for this, but usually you get what you pay for.
In the end, there are piles of old worn out cars that are sitting in junkyards with good engines, so the oil would have to pretty much not be there in order for there to be a big problem.
I have a car that was to have the pistons and rings replaced under the order of a class action lawsuit, if the consumption met the threshold. The consumption was only half of what was required to qualify, and I didn’t like the idea of a dealership rebuild when they struggle to change oil.
I have been using Mobil One 5w40 since I bought it, compression has gone up from 140 to 165 psi, and it runs strong, so I’m happy with it.
That can be a big surprise to put thin oil in a worn out engine, have had some of those that would smoke with cheap 10-40, yet perfect with 20-50.
As for the wear that one may suspect from a lower viscosity oil, that can be helped with better additives.
I would be concerned that more average quality oils would have additives that would not hold up as well in either the lower viscosity or with a huge split in viscosity rating. Maybe technology has helped here and allowed for this, but usually you get what you pay for.
In the end, there are piles of old worn out cars that are sitting in junkyards with good engines, so the oil would have to pretty much not be there in order for there to be a big problem.
I have a car that was to have the pistons and rings replaced under the order of a class action lawsuit, if the consumption met the threshold. The consumption was only half of what was required to qualify, and I didn’t like the idea of a dealership rebuild when they struggle to change oil.
I have been using Mobil One 5w40 since I bought it, compression has gone up from 140 to 165 psi, and it runs strong, so I’m happy with it.
And then how is it explained that in current engines no more periods of settlement are needed ?
I noticed that Ford and GM stated they have no plans for switching to the lighter oil in that article.
It might have been marketing, but I have seen several videos ("Modern Marvels" ?) on automobile manufacturing at specific plants in which they claim the modern manufacturing tolerances are much tighter than in the past (referring to the 70s).
It might have been marketing, but I have seen several videos ("Modern Marvels" ?) on automobile manufacturing at specific plants in which they claim the modern manufacturing tolerances are much tighter than in the past (referring to the 70s).
That tv show was likely referring to tooling and automation enabling tighter gaps in body panels etc. not internal engine clearances.
New engines still free up after a few thousand miles, nothing has changed there, you were always advised to take it easy on a new engine, and now they may run them in a bit at the factory to help prevent bad things from happening. We had an 8,000 rpm Acura that advised in the manual to not beat it too hard for some amount of miles I recall. That car engine loosened up at around 5K miles, which is typical.
Many years ago there was non-detergent oil for the purpose of allowing rings to seat, but that went away at some point. Never saw the merit in doing that and risking a new camshaft myself.
Maybe some better coatings on pistons, piston construction, better ring materials, but the running clearances are the same. Nothing that a lower viscosity oil is going to change.
The engine parts still have mass and expand and contract the same as always.
Look up recommendations for oil on North American Toyota’s vs those in Ireland and Australia, can choose a vehicle that is sold with the same engine in all those areas and then check the specs from the manufacturer; one says to use 0W-XX, while the other says 5W-XX.
New engines still free up after a few thousand miles, nothing has changed there, you were always advised to take it easy on a new engine, and now they may run them in a bit at the factory to help prevent bad things from happening. We had an 8,000 rpm Acura that advised in the manual to not beat it too hard for some amount of miles I recall. That car engine loosened up at around 5K miles, which is typical.
Many years ago there was non-detergent oil for the purpose of allowing rings to seat, but that went away at some point. Never saw the merit in doing that and risking a new camshaft myself.
Maybe some better coatings on pistons, piston construction, better ring materials, but the running clearances are the same. Nothing that a lower viscosity oil is going to change.
The engine parts still have mass and expand and contract the same as always.
Look up recommendations for oil on North American Toyota’s vs those in Ireland and Australia, can choose a vehicle that is sold with the same engine in all those areas and then check the specs from the manufacturer; one says to use 0W-XX, while the other says 5W-XX.
The "W" rating is the SAE viscosity curve it sits on at 0C. The second number the curve at 100C. The oil is not thinner at 0C than it is at 100C, it's merely thinner relative than if it were a straight viscosity. Since passenger cars target around 100C, it is a misconception that any oil is too thin at startup; it is still thicker than ideal, even a 0w. Generally speaking, a 5W-40 is in theory not any thicker than a 0W-40 once the car is warmed up, and it performs better on startup. Now, in practice a 0W-40 is slightly thinner than a 5W-40, but it still must meet SAE specs for 40 grade or it could not be labeled it. A 0W-xx is often a better oil than the 5w-xx version because to get the 0W it needs a fancier base stock or VII additives.
A 0W-40 is way thicker than a 5W-20. Go pour both into a beaker, even cold. The 0W is only thinner well below freezing. If you have problems with thin oil, look to the second number.
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Yes, many engines are actually redlined at the factory. The only new cars (that I can recall) that carry official break-in instructions and an early service are some Porsches and BMW M cars. They are subjects of much debate. It is in all likelihood a leftover warning to prevent doctors and lawyers from wrapping their 400+ HP cars around trees in the first month of ownership.
Yes. Straight oil's viscosity drops more than 1000:1 from 0 to 100. It varies so much it is never optimum (except by accident).
Fortunately the optimum is broad. Viscosity in a beaker is different from why bearings build self-pressure under a dynamic load. Very cold thick oil slows a starter which is already slow from a cold battery. Very hot/thin oil requires a bigger oil-pump than the maker wants to put in (also excess pumping loss when oil is more normal).
Let me guess, your Acura was an RSX Type S with a K20 engine. Nice engine.
The hot viscosity of the oil is what determines clearances and those definitely have gone down as manufacturing tolerances have improved and the industry has broadly switched to 20 weight oils. Further, many older or high performance engines like your K20 were not ALL aluminum, they had cast iron cylinder sleeves even when they had an aluminum block. The sleeves then have a different thermal coefficient of expansion than the bores. The most modern engines don't use cylinder liners and are made of AluSil or similar.
Yep, the oil pressure / flow is what's important if I recall correctly, as far as plain bearings go. If you are relying on leftover film strength to protect you, you're in trouble.
I had a car with the BMW S54 engine (100 hp/L NA, undersquare, 8k redline) which was known to eat rod bearings. You can put whatever oil you like in them, but the bearings never look good when they are pulled after 100k miles. BMW panic switched everyone to Castrol TWS Motorsport 10W-60 but there is no evidence it actually helps and it is thicc for the street
. On that engine I'm not sure if anyone conclusively got to the bottom of it, but on the later high revving V8 and V10 some guys redesigned the bearings and got Mahle Clevite to make a batch for increased clearance and tweaked eccentricity. The clearances were very tight for engines that came with 10W-60 factory fill.
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I grew up in a racing family (stock car,drag,mx,enduro/gncc) used to use straight 30w because multi vis breaks down faster and the bigger the difference between the first and second numbers the quicker it happens.
The best thing you can do for longevity is find the highest ppm of zddp in whatever viscosity recoed.
This was getting hard to find and I think the last oil we used was royal purple (not for sure though) many specialty oils still have zddp.....I think shell aviation oil had high levels in its ad pack but your talking over 15 yrs ago!
zddp is where it’s at.
The best thing you can do for longevity is find the highest ppm of zddp in whatever viscosity recoed.
This was getting hard to find and I think the last oil we used was royal purple (not for sure though) many specialty oils still have zddp.....I think shell aviation oil had high levels in its ad pack but your talking over 15 yrs ago!
zddp is where it’s at.
Without questioning your opinions (although you don't mention what Royal Purpose costs extra), since modern engines seem to outlast the rest of the car even for cars owned by negligent maintainers.... there have to be other matters to fret about rather than finding the perfect oil.
Stated differently, can anybody point to trustworthy evidence that it makes any difference between the better and the worser oils for longevity? Or performance?
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