Throw in some 0W-20 if those machines if not driven hard or on the track.
Engine Damage caused from 0W20/5W20?
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HTHS is really only defined as the viscosity at 150C and a shear rate of 1 million/sec. The correct statement would be that the thicker oil will still have a higher dynamic viscosity (cP) at elevated temperature than a thinner oil will at a lower temperature. The bottom line is that a thicker oil, even if it runs a few degrees hotter than a thinner oil under the same exact conditions will still give more wear protection from the viscosity factor. Viscosity is always the main factor to keep moving parts separated by "Riding the Film" (like that old 1937 movie short - LINK) which is what makes lubrication happen.
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2nd revival now
Triple_Se7en
$50 Site Donor 2024
Folks! Don't try this unless you own a Toyota or Honda.
(Primo Solution?).......A Hybrid from either manufacturer is the ultimate reward for supplying fleet vehicles with great fuel economy to your workers and rental customers.
Also the folks complaining about old posts that re-surface/should have been locked...post responses
When someone asks "what oil for this engine" then I ask what is your lowest expected start temperature, what's the run temperature and then what are you going to do with it.
Why would I do that? We have 5/6 vehicles that are VAG and all call for 502 (or could run 504 reverse) oils so no-go on 20 grades even for non-track use. The 6th and only non-VAG vehicle in the fleet? 5W20 for the last 13 years/140K miles....and it gets autocrossed. Thought about running a 30 to be in the BITOG super-cool thickie club but figured why make a break for what has been working? This argument is similar (except for cost) to telling eveyrone to run 93 vs. 87 regardless of what the car's ECU is tuned for b/c why wouldn't it always be a good idea to have more knock/pre-ign head room? Even for just driving that Corrola to the grocery store.Throw in some 0W-20 if those machines if not driven hard or on the track.
When I was running a 40 weight oil in my pressure washers and the first time I stuck the thermometer dipstick in there and it hit 260F I switched to a 50 weigh. As far as I can tell on the gauge it doesn't appear to be running any hotter after switching to 50 weight. It may be running 1 degree C hotter. Whatever it is it's not enough different to make a difference and I'm definitely better off putting 50 weight in them.
Just throwing this out. My max temperature recorded while towing with my Q7 was roughly 260 degrees F. Probably closer to 257 but my memory may have been corrupted. This is with Mobil 1 0w-20. What makes it interesting is that the oil thermostat does not fully open until 257 F. I’m sure this exactly what the Audi engineers planned.
I suppose I'm an "actual engine engineer" by professional qualification, but my experience is in high pressure fuel injection systems and air handling (turbos, intakes, etc) , so I'm out of my lane when speaking to the kinds of concerns most of us have when it comes to the wear of hard parts in the power cylinder and the overhead: rings, bores, bearings, cams, etc. I work with real experts on these parts-- several I'd consider friends. But I am not an expert and have only peripheral experience.
Also, I work for a large mostly-diesel engine maker (that rhymes with "summons") and obviously, diesel engines are not gasoline engines. That said, I've seen a lot of engine hardware torn apart. Just yesterday I was inspecting engine parts from a teardown and saw all the hard parts one could care about. I've seen more post-test engine parts than most.
I work primarily now in large industrial engines 600-5100hp where cost per operating hour is the most important factor. Fuel is the largest operating cost per hour by far--nothing else is close.
I'm always haunted by a question that seems not to go away: if thinner oils saved enough fuel to be cost-effective, why are they not used by huge mining concerns who track operating costs to the penny?
For example: Rio Tinto operates literally hundreds of mining haul trucks (Komatsu 980s, typically with our 78L V18 at 3500hp) and dozens of excavators digging commodity minerals from the earth around the clock. They have no pricing power in the market-- ores are commodities. So their entire profitability comes from cost management. Thus, they are incredibly diligent in tracking costs and in value assessment.
Rio is very forward thinking to drive value creation. They test prototype filter media for us. They fit their trucks with dataloggers that send data to our cloud. They experiment with fuel additives, oil drain intervals, oil types, etc. They do not necessarily follow formal recommendations from us as the OEM for their engines-- there are cases where they have led us to adopt particular revisions to our formal guidance. They are forward thinking and always pushing ahead.
Importantly, Rio Tinto is focused on cost per hour. They are NOT just focused on fuel economy for meeting a government test profile or CAFE. Nor are they focuses solely on maximizing life and ignoring fuel economy.
They monitor fuel expenses very carefully, but they also monitor engine life and time to overhaul. If it was cost effective to sacrifice 5000 hours of LTO in return for 2% fuel economy, they would do it.
A typical QSK78 in their fleet will burn over $4M worth of fuel before it is overhauled at 20k-25k hours. A 2% fuel economy savings is $80,000 per engine and buys a big chunk of the parts needed for overhaul.
So why is Rio still using a 15w-40 oil? Don't they know they could switch to a diesel rated 10w-30 or 5w-30 and save the tons of fuel while saving the planet? Why haven't they experimented with a 20wt oil?
These engines are about 180lb-ft per liter of displacement. So the cylinder pressure is higher than most NA engines, but not too far from what a modern TGDI gasoline engine would have. My 2.0T Honda is 140lb-ft per liter, and even as low as 1500rpm.
Also these diesel engines are turbocharged and direct injected. Oil temperatures are similar to what a modern gasoline engine will run, perhaps even lower (240F is typical).
Isn't it curious that they persist with 15w-40 when we're told that thin oils are the way to go for fuel economy with plenty of durability?
Also, I work for a large mostly-diesel engine maker (that rhymes with "summons") and obviously, diesel engines are not gasoline engines. That said, I've seen a lot of engine hardware torn apart. Just yesterday I was inspecting engine parts from a teardown and saw all the hard parts one could care about. I've seen more post-test engine parts than most.
I work primarily now in large industrial engines 600-5100hp where cost per operating hour is the most important factor. Fuel is the largest operating cost per hour by far--nothing else is close.
I'm always haunted by a question that seems not to go away: if thinner oils saved enough fuel to be cost-effective, why are they not used by huge mining concerns who track operating costs to the penny?
For example: Rio Tinto operates literally hundreds of mining haul trucks (Komatsu 980s, typically with our 78L V18 at 3500hp) and dozens of excavators digging commodity minerals from the earth around the clock. They have no pricing power in the market-- ores are commodities. So their entire profitability comes from cost management. Thus, they are incredibly diligent in tracking costs and in value assessment.
Rio is very forward thinking to drive value creation. They test prototype filter media for us. They fit their trucks with dataloggers that send data to our cloud. They experiment with fuel additives, oil drain intervals, oil types, etc. They do not necessarily follow formal recommendations from us as the OEM for their engines-- there are cases where they have led us to adopt particular revisions to our formal guidance. They are forward thinking and always pushing ahead.
Importantly, Rio Tinto is focused on cost per hour. They are NOT just focused on fuel economy for meeting a government test profile or CAFE. Nor are they focuses solely on maximizing life and ignoring fuel economy.
They monitor fuel expenses very carefully, but they also monitor engine life and time to overhaul. If it was cost effective to sacrifice 5000 hours of LTO in return for 2% fuel economy, they would do it.
A typical QSK78 in their fleet will burn over $4M worth of fuel before it is overhauled at 20k-25k hours. A 2% fuel economy savings is $80,000 per engine and buys a big chunk of the parts needed for overhaul.
So why is Rio still using a 15w-40 oil? Don't they know they could switch to a diesel rated 10w-30 or 5w-30 and save the tons of fuel while saving the planet? Why haven't they experimented with a 20wt oil?
These engines are about 180lb-ft per liter of displacement. So the cylinder pressure is higher than most NA engines, but not too far from what a modern TGDI gasoline engine would have. My 2.0T Honda is 140lb-ft per liter, and even as low as 1500rpm.
Also these diesel engines are turbocharged and direct injected. Oil temperatures are similar to what a modern gasoline engine will run, perhaps even lower (240F is typical).
Isn't it curious that they persist with 15w-40 when we're told that thin oils are the way to go for fuel economy with plenty of durability?
Not sure the use of HD earth moving equipment in the mining industry is a valid one w/r to the thin/thick (20 or 30 grade) debate here for someone's Toyota but then again, many BITOGers swear by Brotella T6 5W40 diesel oil in everything
15W40 HD diesel oil is mostly what I see on the service trucks at the mining operations I work at. I would think 5W30 is common in the northern climates say in Canada. To me your question is about use, mining equpiment is "extreme duty" and like vehicles used on track, v. low grade oils aren't appropriate. Not the same as the folks that come on here going on and on about their XYZ Kia they are worried about running a 20 grade in where they probably never get to 5K RPM and folks telling them run a 30 or it will have increased wear/cause longevity issues.
No disagreement there-- I'm not asserting that their use directly applies, and I'd hoped my post contained sufficient disclaimers to preclude the suggestion I was making emphatic statements of fact about thick vs thin.Not sure the use of HD earth moving equipment in the mining industry is a valid one w/r to the thin/thick (20 or 30 grade) debate here for someone's Toyota but then again, many BITOGers swear by Brotella T6 5W40 diesel oil in everything
15W40 HD diesel oil is mostly what I see on the service trucks at the mining operations I work at. I would think 5W30 is common in the northern climates say in Canada. To me your question is about use, mining equpiment is "extreme duty" and like vehicles used on track, v. low grade oils aren't appropriate. Not the same as the folks that come on here going on and on about their XYZ Kia they are worried about running a 20 grade in where they probably never get to 5K RPM and folks telling them run a 30 or it will have increased wear/cause longevity issues.
It might be an "extreme" duty cycle comparable to racing, but I think 240F oil temps sort of dispel that comparison. Rather the relevant "Extreme" I find most interesting is the extreme attention to fuel economy and cost that has yet remained insufficient to get them off a 15w-40.
If the protection was equal and the fuel savings real, why don't they run the thinner oils? Across their fleet of trucks and excavators, even a single percentage point would be a million bucks a year.
At the mine sites we support in Canada, they still use a 15w40 until you get WAY up north where they use a full synthetic (Shell rimula Ultra 5w-30).
We have a lot of mining customers in South America where the equipment operates at very high altitude (10,000ft plus) and temperatures get brutally cold. And they still run the 15w-40.
What do they know about fuel economy and operating costs that government regulators seem not to know? Or what does the government know about reliability and durability that these fleet managers seem not to know?
I don't have a good answer for that. But it does suggest to me that two factors are at work here: 1) mining fleet managers are so risk averse that the will eat a fuel economy penalty before they risk premature failure or shortened LTO-- they stick with what they know (like most of us). 2) The energy behind lighter oils is perhaps pressing them because they care about fuel economy and not so much about durability.
And likely a third factor: viscosity doesn't matter as much as we think it does.
How do you know running that 5W-20 is really "working" good enough to provide full protection? Sure, it's not going to blow up and put a rod through the block, but it could be causing a bit more wear. Of course, auto-cross is short lived engine beating, so the oil temps probably don't get more than a few degrees higher after a 60 second or less auto-cross run. Take it to the track and run a 30 minute session at near redline and see how it does. I still recall a guy on YT who thought it was a good idea to run 5W-20 at the track because he thought "the oil temps would stay lower", then after a few track sessions he took the oil pan off and looked at his journal bearings and wondered why they showed so much wear, lol.
Your example of using 93 vs 87 octane is more along the lines that corresponds to running xW-30 vs xW-20. Why would you want to run something that gives less engine protection than more in conditions where it could make a difference. Why would you run a fuel with less octane that could cause more knock than a higher octane fuel that wouldn't.
Exactly ... the slight increase in oil temp compared to a thinner oil still leaves a lot of room for the thicker oil to still provide more MOFT between moving parts and therefore more wear protection.
CAFE doesn't really care about engine longevity. Motorcycles don't have to abide by CAFE, and look at what oil weight they use ... primarily 10W-40 even if they are water cooled and have an oil cooler on them. If 0W-20 was so great, why don't motorcycle makers spec thin oil for them (rhetorical question of course).
Exactly. There is zero emphasis on reliability and durability in the EPA fuel economy testing.
How would you know that running 30 is providing "full protection" and reducing wear without a tear down? Why not 40 for even more protection? I wasn't talking about taking it to the track, I was talking about normal use with some autocross which already far exceeds the typical BITOGer's use that is invovled in these discussions. Yes, for track use, a 30 would be the way to go but honestly, for that car, 20 would be just fine, it's not a high-power density vehicle...~80 hp/L and no turbo to create heat. My Golf is >200 hp/L with track oil temps of 270 deg F+ so a quite a bit different. I know several folks running VW508 20s on track in their MK7/8 GTIs.
Yes, that's why I gave it as an example.
So you run 93 in your vehicles that are rated to be able to run on 87 min. regardless b/c you want extra knock head room even if it's not needed? I run 93 in my vehicles that require it, not the ones that don't.
xW-30 is going to give more engine protection regardless ... that's the whole purpose of stepping up a grade. I like headroom, not possibly running on the ragged edge in some situations. Have you tore it down to verify all the bearings are not showing any undue wear?
Re: bold above. So you're saying you think a xW-20 would be fine for that car in track use just because it's a low-density engine? It depends on a lot more than just that factor. Any of your race folks ever tear open those engines used for track use with 20 to inspect bearings? Just because an engine doesn't blow a rod through the block doesn't mean it's wearing out faster.
Yes, I do on the Coyote V8 even though it will run on 87. I also run 5W-30 instead of 5W-20 ... such a rebel !
I made the switch to 5W-30 way before Ford finally woke up and started specifying 5W-30 not long ago for the Coyote in the USA. Apparently the switch to a higher viscosity by Ford was going to sacrifice CAFE credits for something better.
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That’s fair, and reasonable. Gold star for you today!
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