i am going to run the manufacturer's suggested grade in everything i have until the day i actually wear an engine out. at that point, i will maybe reconsider.
Why does xw20 and xw30 show essentially the same/similar UOA but people blame cafe?
- Thread starter jalikaria24
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What's wrong with added MOFT headroom/protection? The argument is nothing ... not that 5W-20 will "blow-up" your motor, but it could cause slightly more wear depending on use conditions compared to a thicker oil based on technical studies. Not trying to say using xW-20 is "bad", and I don't care what others use.
I'll rephrase the question. When I see an engine running fine with 350,000 miles that's been run exclusively on xW20 oil, why do people still blame CAFE and cry for Xw30?
That's a better way to ask it.
That's a better way to ask it.
sounds like proper and consistent maintenance more than anything.
my guess - if you know enough to be confident that a 30 wont hurt and think the added wear protection is worth the minimal fuel economy hit, why not? for me and other average joes, doing the research and becoming confident enough to deviate from the OEM rec isn’t worth the effort.
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Blackstone has stated many times in the comments section on their uoa's that show high wear metals to bump up the viscosity and run another uoa to compare.
Nobody is "blaming" CAFE for anything except to push xW-20 in OMs and on oil fill-caps in many vehicles that use to spec xW-30 weight or higher in order to make people think that their car was specially engineered around an oil viscosity. And we know that's not true from the many OMs for the same cars sold in other countries showing a whole spectrum of acceptable viscosity. And many studies show that using thicker oil can give more wear protection. It just so happens that most vehicles will last a very long time on xW-20, so it makes it even easier to push the thinner oil - rightly so in relatively benign use conditions. As you know if reading a lot here, a few manufacturers have went back to xW-30 on vehicles where they use to recommend xW-20. Ford did that for the 2021+ 5.0L Coyote V8 in the Mustang and F-150. Previous years specified 5W-20. Go figure ... could be the engineers knew 5W-30 gives more engine protection - what else would be the reason. IMO, the Coyote should have had 5W-30 since the begging ... but it took Ford 10 years to get to that point.
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OVERKILL
$100 Site Donor 2021
This sounds remarkably similar to a recent oil filter discussion...
You and your headroom obsession! When headroom is ample, more doesn't help.
If you came to a low underpass marked 10-foot clearance while driving a sub-5-foot high vehicle, I suspect you'd drive miles out of your way to avoid it, to be certain you had enough headroom to please you.
LoL, bad analogy. What if the clearance was only 6 inches and the height of your vehicle and the overpsss kept changing due use conditions and environment where that 6 inches went to zero. MOFT doesnt stay constant. I think the concept of headroom wrt MOFT went over your head.
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What exactly are you talking about "blaming cafe". The move to lighter oils for mileage is not speculation, it is fact. It is directly to blame for the mass switch and back specing to 0/5w-20.
That is an entirely different topic from does 0w-20 protect as well as 5w-30 which is futile to debate amongst us. Does astm testing not have definitive results? I'm sure each oil group knows the answer to this amongst THEIR formulas (of same and different weights) but it's not info we'll probably every get.
That is an entirely different topic from does 0w-20 protect as well as 5w-30 which is futile to debate amongst us. Does astm testing not have definitive results? I'm sure each oil group knows the answer to this amongst THEIR formulas (of same and different weights) but it's not info we'll probably every get.
4WD
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UOA’s here are a bit on the hobby side. Take large industrial engines. OEM “prescription“ for everything … sample taken from cooling loop (not sump samples) when hot and under load. Oil specifications must be followed.
(Many don’t switch to another oil). Oil must be changed at —- hours.
That UOA must meet OEM’s criteria - and even that will not buy you more hours on an oil change.
For UOA’s here to not be all over the place - something similar needs to happen.
(Many don’t switch to another oil). Oil must be changed at —- hours.
That UOA must meet OEM’s criteria - and even that will not buy you more hours on an oil change.
For UOA’s here to not be all over the place - something similar needs to happen.
4WD
$50 site donor 2024
I think most here got my point … you again make oblique comments to get back on your standard narrative
Yes! Use a 20 or even 16 grade if your car is designed to use it and fuel economy is the most important factor for you, just be aware that a thicker oil might offer better protection in extreme conditions and realize it will not blow up your engine if you deviate from the oil caps recommendation.
Could there be any other variables causing older vehicles to remain on the roads, longer?
Perhaps consumers rejecting new tech? Or consumers unable to afford new vehicles? Or vehicles built, say 15-20 years ago, were just "that good" to last longer? Or, in the last 18 months, people reduced commuting by 50% or more, so vehicles were made to last longer? Maybe the oil is the determining item, but maybe it's not.
Nobody has to believe the facts around it. People typically make decisions based on facts. But some do based on feelings and antidotes (ie, it didn't blow-up or went 200K miles and still "runs good"), but it's all good.
Seems that people who hear that thinner oil gives less MOFT and possiby less wear protection in some use conditions get upset over it.
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I'm in two camps on this.
1. I like the heaviest oil that is not a detriment. I do not care at all about minor MPG differences.
2. I suspect any oil in the general range will be fine, and the engine will probably outlast the rest of the car such as body, frame, interior, electronics, etc. when it finally goes to the grave with a good high miles engine but destroyed (insert - interior, transmission, body, frame, etc.).
1. I like the heaviest oil that is not a detriment. I do not care at all about minor MPG differences.
2. I suspect any oil in the general range will be fine, and the engine will probably outlast the rest of the car such as body, frame, interior, electronics, etc. when it finally goes to the grave with a good high miles engine but destroyed (insert - interior, transmission, body, frame, etc.).
Maybe it’s the region you live in? Where I live newer cars are the norm. Older cars, say 15 years or older are becoming less and less.
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