SHELL Full Synthetic 5w-30 : Yaris 4,705 miles ...
- Thread starter odie
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Thank you, odie, for your series of UOAs on your Yaris. I am looking forward to your 5W-20 UOA. The main concern with going to a possibly too thin viscosity is possibility of increased bearing wear, which would show up as increased lead levels in the UOA. This is because the minimum oil-film thickness (MOFT) in the bearings is proportional to the HTHS viscosity (only 2.6 cP for 5W-20). It will be interesting to see how your bearings will do with 5W-20. I am looking forward to it and please keep us updated.
Originally Posted By: odie
Welcome , not too concerned about extra wear . Have seen other UOAs from this site of 5w-20 oils used in the 1.5 ltr. with good results . Keep our fingers crossed .
I really like your careful systematic approach and detailed information. And thumbs up for keeping the faith on the Toyota 90915-YZZF2 oil filter like I do!
My guess is that the oil temperature in Toyota engines doesn't get too high. If the oil temperature is not too high, then, even with xW-20, the oil won't get too thin and it won't result in bearing damage. It's not the SAE viscosity that protects the bearing -- it's the actual HTHS viscosity, which depends on the oil temperature.
Again, I'm looking forward to your 5W-20 UOA to see if the lead level (bearing wear) will change! Thanks for your series of UOAs, odie!
PS: I was going to do a UOA for the first time for my Mobil Delvac 1300 Super 15W-40, but because of the little clerance between the oil pan and the oil-drain container, while trying to take it out, I ended up overturning and spilling the entire bottle filled with hot oil in my hand and screamed. LOL Perhaps next time it will be successful.
Welcome , not too concerned about extra wear . Have seen other UOAs from this site of 5w-20 oils used in the 1.5 ltr. with good results . Keep our fingers crossed .
I really like your careful systematic approach and detailed information. And thumbs up for keeping the faith on the Toyota 90915-YZZF2 oil filter like I do!
My guess is that the oil temperature in Toyota engines doesn't get too high. If the oil temperature is not too high, then, even with xW-20, the oil won't get too thin and it won't result in bearing damage. It's not the SAE viscosity that protects the bearing -- it's the actual HTHS viscosity, which depends on the oil temperature.
Again, I'm looking forward to your 5W-20 UOA to see if the lead level (bearing wear) will change! Thanks for your series of UOAs, odie!
PS: I was going to do a UOA for the first time for my Mobil Delvac 1300 Super 15W-40, but because of the little clerance between the oil pan and the oil-drain container, while trying to take it out, I ended up overturning and spilling the entire bottle filled with hot oil in my hand and screamed. LOL Perhaps next time it will be successful.
There will be over 2,000 miles on the oil this weekend . TOYOTA posted an approval for the 5w-20 about 4 years ago . Have a signed e-mail from service center assistant where we bought the car new for the use of the 5w-20 in the YARIS . We have faith in SHELL / SOPUS oils . Been using it for years .
Originally Posted By: odie
There will be over 2,000 miles on the oil this weekend . TOYOTA posted an approval for the 5w-20 about 4 years ago . Have a signed e-mail from service center assistant where we bought the car new for the use of the 5w-20 in the YARIS . We have faith in SHELL / SOPUS oils . Been using it for years .
SOPUS products -- Rotella, Pennzoil, Quaker State, Formula Shell, and as well as their maintenance fluids and car-care products -- are definitely some of the top-rated products out there. In theory, currently in USA, Pennzoil is supposed to be of slightly higher quality than Quaker State, which is in turn supposed to be of slightly higher quality than Formula Shell, but the real-world results can vary.
Your UOA is going to be a much better assurance on how well 5W-20 is doing in your engine than any official Toyota statement.
There will be over 2,000 miles on the oil this weekend . TOYOTA posted an approval for the 5w-20 about 4 years ago . Have a signed e-mail from service center assistant where we bought the car new for the use of the 5w-20 in the YARIS . We have faith in SHELL / SOPUS oils . Been using it for years .
SOPUS products -- Rotella, Pennzoil, Quaker State, Formula Shell, and as well as their maintenance fluids and car-care products -- are definitely some of the top-rated products out there. In theory, currently in USA, Pennzoil is supposed to be of slightly higher quality than Quaker State, which is in turn supposed to be of slightly higher quality than Formula Shell, but the real-world results can vary.
Your UOA is going to be a much better assurance on how well 5W-20 is doing in your engine than any official Toyota statement.
I agree with Jim Allen, a TBN of 3.1 is not low. It looks like all of the new SN synthetics are starting out with a much lower TBN than in the past, some in the low 6's. But, the new oils also appear to be holding their TBN longer than previous formulations.
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Originally Posted By: wag123
I agree with Jim Allen, a TBN of 3.1 is not low. It looks like all of the new SN synthetics are starting out with a much lower TBN than in the past, some in the low 6's. But, the new oils also appear to be holding their TBN longer than previous formulations.
TBN ~ 3 is about typical of most SM or SN gasoline-engine oils after 5000 miles and should be sufficient. TBN retention is provided by magnesium, which is standard in HDEOs, as these oils are meant for much longer drain intervals. Magnesium is also used for TBN retention in Mobil 1 Extended Performance. Nowadays, magnesium is also used in 0W-20 oils, since the car manufacturers specify 10,000-mile oil-change intervals for 0W-20.
The drawback of magnesium is the possibility of increased wear and corrosion. That's why it's usually avoided in most PCMOs, as most PCMOs -- regardless of being conventional or synthetic -- are meant for 5,000-mile oil-change intervals.
See more discussion of TBN retention and magnesium here, which also has a reference paper.
I agree with Jim Allen, a TBN of 3.1 is not low. It looks like all of the new SN synthetics are starting out with a much lower TBN than in the past, some in the low 6's. But, the new oils also appear to be holding their TBN longer than previous formulations.
TBN ~ 3 is about typical of most SM or SN gasoline-engine oils after 5000 miles and should be sufficient. TBN retention is provided by magnesium, which is standard in HDEOs, as these oils are meant for much longer drain intervals. Magnesium is also used for TBN retention in Mobil 1 Extended Performance. Nowadays, magnesium is also used in 0W-20 oils, since the car manufacturers specify 10,000-mile oil-change intervals for 0W-20.
The drawback of magnesium is the possibility of increased wear and corrosion. That's why it's usually avoided in most PCMOs, as most PCMOs -- regardless of being conventional or synthetic -- are meant for 5,000-mile oil-change intervals.
See more discussion of TBN retention and magnesium here, which also has a reference paper.
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