Thin or thick (TGMO 0W-20/M1 0W-40): Final verdict

[OVERKILL]

Originally Posted By: ZeeOSix
Originally Posted By: OVERKILL
So then the question becomes, since SAE 0w-5 doesn't exist, what are the viscosity characteristics of this product? The results in the graph, which are tied to the cited grades, become less useful when one of the grades is made up and has no binding parameters for visc, HTHS...etc due to not being a part of the SAE J300 rating system.


The other oils in those graphs don't list exact viscosity, HTHS, etc either. What the article is showing is those graphs are trends so the reader can see which way things go depending on what oil "viscosity" is used. 0W-5 would obviously be the most viscous oil at operating temperature in the bunch.


No, but we know, due to J300, what range of visc those oils fall within. That 0w-5 could be anything below the upper limit for 0w-20, giving us a pretty wide spread to contrast to the 10w-30 for example. And I think you mean the least viscous

 

[ZeeOSix]

Yeah, least viscous of course.

The article is to just show what the trends are when viscosity changes. They probably did show "0W-5" (real or not) so the difference was drastic enough to show the trend. Same reason they probably used a 10W-60 on the upper end.

 

[OVERKILL]

Originally Posted By: ZeeOSix
Yeah, least viscous of course.

The article is to just show what the trends are when viscosity changes. They probably did show "0W-5" (real or not) so the difference was drastic enough to show the trend. Same reason they probably used a 10W-60 on the upper end.


For sure, and I'm not disputing that. I would just have liked to have a real grade represented so I knew the parameters.

 

[Gokhan]

Back to thin or thick.

I got the results for the OCI with TGMO 0W-20 SN after the OCI with M1 0W-40 SN. They are similar. The verdict could be that the oil viscosity doesn't matter that much. I may try a 15W-40 HDEO this time to see what happens. This will be a very long trial.

UOA (link): TGMO 0W-20 SN (Toyota), TBN/TAN, 5142 M, 85 Corolla 4A-LC

1985 Toyota Corolla LE, 4A-LC engine
Mobil 1 Extended Performance M1-103 oil filter
5142 miles and 622 days on oil (yes, almost two years)
Mostly short trips (probably hard on oil)
Sampled through the dipstick using the Blackstone vacuum pump
Oil level was about 0.3 quart low, slightly more consumption than the previous 0.2 quarts
No makeup oil used
UOA by Wear Check
Oil used was TGMO 0W-20 SN ©2015. It turned out that it had no high moly and probably no GTL either!

The results are similar to those in the past, including for M1 0W-40, except for copper, which came almost twice as much this time. Lead was low. Aluminum was low. Chromium is still a tad bit high. Iron is normal. TAN and TBN are both good.

It's hard to say whether thick or thin is better. However, M1 had the best results on chromium. Perhaps I'll try a thick 15W-40 this time to see what it does.

I'm not sure if the premium, high-efficiency oil filter helped but lead was good.

I also don't know where the extra copper came from but perhaps there was some bearing wear.

It looks like the coolant seep has stopped.

 

[badtlc]

any noticeable impact on startup, engine noise or MPGs?

 

[Shannow]

Gohkan,
for your next experiment, rather than going all the way to a 15W40 and changing a heap of variables, how about Amsoil ACD..."straight grade 30, no VIIs, still 3.6 HTHS, so comparable to M1 0W40, and still a synth ???

 

[SatinSilver]

^ That's not a bad idea from the poster above. ^

 

[ChemLabNL]

Originally Posted by Shannow
Gohkan,
for your next experiment, rather than going all the way to a 15W40 and changing a heap of variables, how about Amsoil ACD..."straight grade 30, no VIIs, still 3.6 HTHS, so comparable to M1 0W40, and still a synth ???


Agreed. That one looks like a great oil.

 

[dave1251]

The premise of this thread is meaningless at best. If the oil tempatures are too high to thin a 20 grade to the point it can't protect then a 40 grade is better. In everyday American commutes this is not going to happen unless there is an mechanical failure and the least important factor is having a 40 grade in the sump. If the oil is not getting up to tempature either grade will work with the 20 grade gaining the advantage in the same amount as it's difference in thinness compaired to a 40 grade which is really very miniscule.

 

[Gokhan]

Originally Posted by badtlc
any noticeable impact on startup, engine noise or MPGs?

Certainly, 0W-20 runs smoother, quieter, and gets better MPG than an xW-40.

Originally Posted by Shannow
Gohkan,
for your next experiment, rather than going all the way to a 15W40 and changing a heap of variables, how about Amsoil ACD..."straight grade 30, no VIIs, still 3.6 HTHS, so comparable to M1 0W40, and still a synth ???

It's an interesting oil -- a VII-free SAE 10W-30 that is also a SAE 30. The downsides are that it costs four times as much as an off-the-shelf HDEO and the additive package is an outdated CI-4 PLUS/SJ. I doubt I would see much benefit from it.

The results of the current TGMO 0W-20 SN UOA are good (for iron [valvetrain] and lead [bearings]) except chromium (ring wear) is still somewhat high and copper (bearings?) also got somewhat high this time. I want to see if the chromium issue can be corrected by a really strong HTHSV, around 4.2 cP or so. It could be that there is a part of the cycle in which the rings need more hydrodynamic support.

Any objections to Delo SDE 15W-40 CK-4/SN conventional (HTHSV = 4.2 cP, phosphorus = 760 ppm) for the next fill?

Other options are M1 15W-50 SN full synthetic (really high phosphorus), Delo XLE 5W-40 CK-4/SN PLUS full synthetic, or a ten-year-old jug of Delvac 15W-40 CJ-4/SM conventional.

 

[PimTac]

Gokhan, you are worried about the chromium levels but in a engine with that kind of mileage, a reading of 4ppm in over 5000 miles is actually pretty good and your trend is stable.

I'm not sure I would worry about anything. This is a very good report.

 

[Gokhan]

Originally Posted by PimTac
Gokhan, you are worried about the chromium levels but in a engine with that kind of mileage, a reading of 4ppm in over 5000 miles is actually pretty good and your trend is stable.

I'm not sure I would worry about anything. This is a very good report.

You're right. The universal averages shown in the last column of the Blackstone report are for 2,600 miles. I ran for twice the mileage as that and also close to two years.

Since the lead is low, the copper probably came from the bushings/thrust washers. It could be some transient effect or even some measurement error.

I would like the chromium to go down to 2 ppm though. I don't if M1 0W-40 helped or it was just coincidence that it gave the least chromium.

Another choice is PPPP Euro 5W-40 A3/B4/SN. It's expensive though.

 

[Bryanccfshr]

As an uncommon alternative to test the low VII finished lube option, you could consider Delo 15w30 severe duty.

Originally Posted by Gokhan
Originally Posted by PimTac
Gokhan, you are worried about the chromium levels but in a engine with that kind of mileage, a reading of 4ppm in over 5000 miles is actually pretty good and your trend is stable.

I'm not sure I would worry about anything. This is a very good report.

You're right. The universal averages shown in the last column of the Blackstone report are for 2,600 miles. I ran for twice the mileage as that and also close to two years.

Since the lead is low, the copper probably came from the bushings/thrust washers. It could be some transient effect or even some measurement error.

I would like the chromium to go down to 2 ppm though. I don't if M1 0W-40 helped or it was just coincidence that it gave the least chromium.

Another choice is PPPP Euro 5W-40 A3/B4/SN. It's expensive though.

 

[batook]

I've been following this thread with quite some interest given that I also run several old Toyota motors with thinner-than-recommended oils. In my 91 Previa, I've been running M1 0W-20 for over 7 years and 50k miles with great results, but I've never run a UOA on it. I do however run oil pressure and temp gauges to make sure the oil never gets too hot and thin to provide adequate protection. The naturally aspirated Previa has a rather tall 4.30 gear ratio at the diff, resulting in pretty high revs of around 4k at 75 mph in 5th gear. However, cruising at these speeds and rpms never causes the oil to exceed 210-220F, or PSI to drop below ~45-50, providing the requisite 10 PSI for every 1k rpms. In fact, the only time I've ever gotten close to trouble was when I was aggressively climbing a mountain pass on I-70 trying to hold 70+ mph in 4th gear with the rpms over 4500. In this case the oil did get too hot, exceeding 230-240F, and the PSI fell to around 38-40, which was too low for comfort, so I backed off and let it cool to normal operating temperatures. My takeaway was that it's totally safe to run the 0W-20 in this motor year-round, even in the manual transmission version, provided you aren't towing a trailer or racing the engine up mountain passes, and if you find yourself in the latter situation, just take it easy and back it off a little.

I'm interested if the OP has ever used an oil temp/pressure gauge during any of the 0W-20 runs in the Corolla? Even if not, by my tests you are probably safe even with sustained freeway driving up to 4,000-4200 rpm. I've been tempted to try lighter weight oil in the 4Y-EC motor of my 88 Toyota van, which like the Corolla, also specs 10W-30 or heavier oil, but with 241k miles, was concerned about increased oil consumption and bottom-end bearing wear. Your results have given me more confidence to give 0W-20 a go in the 88 TV. I think I'll even switch to the TGMO instead of the M1 to benefit from the better add pack. Thanks for all your posts on this topic; it's been interesting.

 

[Gokhan]

Good feedback, batook.

My Corolla specs 36 - 71 psi @ 3000 RPM. I run into similar situations with high RPM with the 19-mile-long 6 - 8% grade south of Las Vegas on I-15. I don't have a gauge.

M1 0W-20 has a better base oil (PAO) than TGMO (Group III).

You can't run xW-20 or xW-30 if you have bad valve-stem oil seals. You would have to opt for xW-40 or thicker to control the oil consumption. I replaced them a while back and it stopped the oil consumption.

Wonders of valve-stem oil seal replacement

 

[Gokhan]

Looking at my UOAs, I am suspecting that the chromium (ring wear) is not a result of low viscosity but low TBN and/or extended drains. When I ran over a year, it looks like the low-TBN TGMO 0W-20 didn't do too well with chromium but when I ran for a shorter time period, it did better. See my UOA history. M1 0W-40 with its high TBN did well.

Here is a scholarly article on this:

Mechanism of Wear Control by the Lubricant in Diesel Engines

Abstract: At today's low oil consumption rates, high speed diesel engines with chromium-faced rings have experienced corrosive wear problems. This report defines the alkalinity required to prevent these wear problems; and the appropriate oil drain interval. In addition, the mechanisms of chromium-faced ring wear are identified. The study is based on three different engine types—direct injection two-cycle (DDA 8V-71TA), direct injection four-cycle (Mack ETAZ 673), and precombustion chamber four-cycle (Caterpillar 1Y73).

So, perhaps I need a thin synthetic oil with high initial TBN. Synthetic base oil and high initial TBN will assure that TBN will stay high throughout the OCI. Any recommendations?

 

[edyvw]

Originally Posted by Gokhan
Good feedback, batook.

My Corolla specs 36 - 71 psi @ 3000 RPM. I run into similar situations with high RPM with the 19-mile-long 6 - 8% grade south of Las Vegas on I-15. I don't have a gauge.

M1 0W-20 has a better base oil (PAO) than TGMO (Group III).

You can't run xW-20 or xW-30 if you have bad valve-stem oil seals. You would have to opt for xW-40 or thicker to control the oil consumption. I replaced them a while back and it stopped the oil consumption.

Wonders of valve-stem oil seal replacement

That part of the road you are talking about has 6-8% grade ONLY at certain locations. 6-8% grade over 19 miles would give you elevation between 6-8000ft.
Highest point at I15 between LA and LV is 4,800ft. It is unremarkable part of the road (difficulty wise) and really not challenging. If you have issues there than you need to check things out in your engine.

 

[Gokhan]

OK, fine, not 6 - 8% throughout but it's a tough grade. It sounds like you've never been there. Read the comments here:

http://wikimapia.org/24673889/Baker-Grade

 

[ChemLabNL]

Originally Posted by Gokhan
Originally Posted by badtlc
any noticeable impact on startup, engine noise or MPGs?

Certainly, 0W-20 runs smoother, quieter, and gets better MPG than an xW-40.

Originally Posted by Shannow
Gohkan,
for your next experiment, rather than going all the way to a 15W40 and changing a heap of variables, how about Amsoil ACD..."straight grade 30, no VIIs, still 3.6 HTHS, so comparable to M1 0W40, and still a synth ???

It's an interesting oil -- a VII-free SAE 10W-30 that is also a SAE 30. The downsides are that it costs four times as much as an off-the-shelf HDEO and the additive package is an outdated CI-4 PLUS/SJ. I doubt I would see much benefit from it.

The results of the current TGMO 0W-20 SN UOA are good (for iron [valvetrain] and lead [bearings]) except chromium (ring wear) is still somewhat high and copper (bearings?) also got somewhat high this time. I want to see if the chromium issue can be corrected by a really strong HTHSV, around 4.2 cP or so. It could be that there is a part of the cycle in which the rings need more hydrodynamic support.

Any objections to Delo SDE 15W-40 CK-4/SN conventional (HTHSV = 4.2 cP, phosphorus = 760 ppm) for the next fill?

Other options are M1 15W-50 SN full synthetic (really high phosphorus), Delo XLE 5W-40 CK-4/SN PLUS full synthetic, or a ten-year-old jug of Delvac 15W-40 CJ-4/SM conventional.


The Delo is a fine choice if not the Amsoil ACD.

Hey Shannow! Just look at the Four-Ball numbers on that ACD! Half a freakin millimeter! Can you believe it!?

 

[edyvw]

Originally Posted by Gokhan
OK, fine, not 6 - 8% throughout but it's a tough grade. It sounds like you've never been there. Read the comments here:

http://wikimapia.org/24673889/Baker-Grade

I have drove that part numerous times. I actually hit 130mph going that grade with VW CC (well, that was limiter). It is absolutely unremarkable difficulty.
Bring your car to Pikes Peak, and than go drive that I15 route. It is not grade that is an issue, it is low elevation that allows still very good heat transfer between cooling system and environment. Once you are above 9,000ft, that is where things can get dicy if your engine has even small problem (or some other weakness will show). Here on I70 in CO, you have grades between 6 and 9%. Nothing remarkable, however, problem is some of those parts of I70 are close to 11,000ft (around Vail area for example) where things better be good in your oil sump and radiator. On top of that, for every 1,000ft you loose 3% of power in your naturally aspirated engine (on average). That is why people like me, who live in high altitude (my house is at 6,864ft) prefer turbo chargers. So at 11,000ft you are looking at some 33% drop in power, much less heat exchange and lower atmospheric pressure.
As for comments, write comment back and tell them to go and get to know their country.