Will Thinner Oils Damage Your Engine?

[ABN_CBT_ENGR]

Whatever happened to the concept that a UOA determines the serviceability of the oil and does not determine engine wear?

It got lost by those who read books/articles but don't actually fully grasp the actual science or actually do it. A mild version of Dunning Kruger.

Also, ALL PdM technologies (UT, VA, OA, Eddy etc. et al) should NEVER be use singularly to make a machine assessment. This is taught in every certification class of every discipline.

Lots of people are well read but don't have the formal training that fills in all the gaps and explains things not covered in the articles.

 

[Zaedock]

Whatever happened to the concept that a UOA determines the serviceability of the oil and does not determine engine wear?

They check out Blackstone Labs and read the home page.

WHY OIL ANALYSIS?
LEARN WHAT'S GOING ON WITH YOUR ENGINE
Oil analysis is a quick, nondestructive way to gauge the health of an engine by looking at what's in the oil. People use oil analysis for different reasons: to see if there are any problems developing, to see if their oil is working well in the engine, and to see if they can run longer oil changes.

 

[ZeeOSix]

If the guy who had severely damaged bearings had a UOA that only used Elemental Spectomity (Blackstone?), then it's possible it would not be able to see catastrophic damage since it can only detect particles ~7um and smaller. If a UOA lab only uses Elemental Spectromity to measure metal wear, then it could also be missing a lot of information on what the actual metal levels are since the measurment size range is so limited.

http://media.noria.com/sites/WhiteP...th Oil Analysis and Contamination Control.pdf

"Elemental spectroscopy is a test that has the distinction of monitoring all three categories — lubricant condition, wear debris and contaminants. A spectrometer is used to measure the levels of specific chemical elements present in an oil.Two types of spectrometers are commonly used. Arc emission spectrometers apply energy in the form of an electric arc to the sample. This excites the atoms into vapor form, creating a spectrum where light is generated. Individual light frequencies in the spectrum are measured and quantified to determine the presence and quantities of specific elements present. The other common type of spectrometer is the ICP (inductively coupled plasma) spectrometer. This operates on a similar principle, except that the energy is applied to the sample by a plasma flame rather than an electric arc. There are typically 20 elements measured by spectroscopy and reported in parts-per-million (ppm) (Fig. 2). These measurements represent elements in solution. Spectroscopy is not able to measure solid particles larger than roughly seven μm, which leaves this test blind to larger solid particles."

"Analytical ferrography is used to separate solid contamination and wear debris from a lubricant for microscopic evaluation. As stated earlier, spectroscopy is not able to measure wear particles larger than 7 μm in size. While particle counting, ferrous wear concentration and DR ferrography are able to detect the presence of larger particles, they cannot qualify their composition or origin. Analytical ferrography is able to identify wear particles, their composition and their origin by visually analyzing them microscopically (Fig. 9)."

Blackstone's website says they only use a "Spectral Exam" in their basic UOA testing, they don't mention analytical ferrography testing.

https://www.blackstone-labs.com/tes...abs.net/Bstone/(S(yxmnfp55g2ws1m55lc3ydp45))/

 

[ABN_CBT_ENGR]

just a little more detailed info for those who may want to know

Most labs offer the full range of tests but there are substantial charges for them and they are done by request (I normally run more for industrial equipment) so you need to specifically ask.

ICP is the routine method mostly currently but the problem ( along with analytical ferrography) is that often these particles do not get captured in the sample as they tend to drop out quickly. ( depends on where in the lube cycle the sample comes from and how long it has had to settle before taking it- that's why we in industry strive for online condition monitoring , which is not realistic for a vehicle)

Even with the data, its rare indeed these can lead to a specific failure mode or component- it just triggers a more detailed forensic examination.

 

[MLRTYME]

 

[ZeeOSix]

^^^ Won't ever see any xW-20 specified for Corvettes. The new C8 specifies 0W-40 (Mobil 1 factory fill).

 

[Simon_G]

He had significant bearing wear, yet no evidence of that in his UOA's because the particles being shed were too large to be picked up by it.

It doesn't work that way.

Gradual bearing wear shows up in UOAs.

Now, if something suddenly shut the oil off and the bearings failed rather suddenly, that's another matter.

 

[Simon_G]

Startup wear is and was always just a myth.

Cold starts

All lubricated machinery can suffer damage from cold starts.

In the 1980s there was rash of engine failures which GM traced to motor oils which did not meet their pour point specs.

 

[Simon_G]

Whatever happened to the concept that a UOA determines the serviceability of the oil and does not determine engine wear?

Blackstone Labs

"Oil analysis is a quick, nondestructive way to gauge the health of an engine by looking at what's in the oil."

Properly regularly done it speaks to both the serviceability of the oil and spots incipient engine problems such as excess wear, bearing wear, fuel or coolant in the oil indicating service problems.

 

[Simon_G]

Then check out Blackstone Labs and read the home page.

Right on.

 

[PimTac]

Blackstone Labs

"Oil analysis is a quick, nondestructive way to gauge the health of an engine by looking at what's in the oil."

Properly regularly done it speaks to both the serviceability of the oil and spots incipient engine problems such as excess wear, bearing wear, fuel or coolant in the oil indicating service problems.

That is done by having the analysis done on a regular basis to see trends develop like fleet maintenance and such.

 

[IndyFan]

^^^ Won't ever see any xW-20 specified for Corvettes. The new C8 specifies 0W-40 (Mobil 1 factory fill).

That really isn´t relevant to anything but cars that are potentially run on the track. There would be no reason under the sun to run that oil in my Pentastar, for example. On the other hand, I don´t know if I´ve ever seen a Vette that was used on the track with over 300k miles on it. But I see Pentastars all the time with 300k that were run in Jeeps on 5w20 and the profile included a good bit of off-roading, which is an entirely different usage profile than a car that is run at a track.

So, just based on this, I´d say thin oil is superior for wear protection. But it isn´t really that simple, is it?

 

[Simon_G]

...I see Pentastars all the time with 300k that were run in Jeeps on 5w20 ...

Without more information that falls into the category of anecdotal evidence.

 

[ZeeOSix]

So, just based on this, I´d say thin oil is superior for wear protection. But it isn´t really that simple, is it?

Not according to studies of viscosity vs wear - so yeah, it's not really "that simple" based on that. When you start pushing engines more and more, then xW-20 certainly isn't going to provide as much protection as a thicker oil. It's all about how much MOFT headroom you have between parts as you keep increasing the engine demands. Drive in a 98% benign manner and thinner oil will be OK, but start pushing things and the protection headroom dissipates more and more until metal-to-metal contract and wear really increases.

I'd rather have more headroom than not.

 

[kschachn]

In the 1980s there was rash of engine failures which GM traced to motor oils which did not meet their pour point specs.

That's not exactly correct. They did "meet" the pour point (which is a reported value) but what it did was to illustrate how pour point did not and does not adequately represent the low-temperature behavior of motor oils. This led to a revision of SAE J300. Because of that today an oil's winter rating is a better indicator of cold weather performance than pour point ever was.

 

[demarpaint]

Not according to studies of viscosity vs wear - so yeah, it's not really "that simple" based on that. When you start pushing engines more and more, then xW-20 certainly isn't going to provide as much protection as a thicker oil. It's all about how much MOFT headroom you have between parts as you keep increasing the engine demands. Drive in a 98% benign manner and thinner oil will be OK, but start pushing things and the protection headroom dissipates more and more until metal-to-metal contract and wear really increases.

I'd rather have more headroom than not.

I'm with you. The little extra margin of protection far outweighs the fuel savings, which I have yet been able to measure.

 

[OilUzer]

In general and also after being on bitog for a while, I have concluded that best is to move up a viscosity grade from what manufacturers specify. i.e. If the owner's manual specifies or recommends xWy, I would use xW(y+10). unless y is 50 or higher.

I would also adjust the x based on the ambient temp and not what the OM says.

since I don't own any xW8 or xW16 cars, that rule still applies.

The above rule applies only to US. I am not sure but i think European OM & recommendations are more on target.

 

[MaDMaXX]

I did find my owners manual terms were interesting.

For the NA engines in the F150 (2012)

To protect your engine and engine’s warranty, use Motorcraft SAE
5W-20 or an equivalent SAE 5W-20 oil meeting Ford specification
WSS-M2C945-A. SAE 5W-20 oil provides optimum fuel economy and
durability performance meeting all requirements for your
vehicle’s engine.

Bold by Ford, not me.

If i then look at the next page, with the same info on it but for the turbo engines....

To protect your engine and engine’s warranty, use Motorcraft SAE
5W-30 or an equivalent SAE 5W-30 oil meeting Ford specification
WSS-M2C946-A.

Both have the same lead up text, and same post text in their respective sections, only the bolded text is additional when mentioning the 5w20 oil Vs. nothing mentioned at all for the TT engine requiring the 5w30 oil.

 

[madeej11]

Look at the KV100 compared to the HTHS.

Petrocan Supreme Synthetic 5w-30 ---- KV100 = 11.3 cSt, HTHS = 3.3 cP
Petrocan Supreme Synthetic 10w-30 --- KV100 = 10.2 cSt, HTHS = 3.2 cP

The 5w-30 is definitely shearing more than the 10w-30. If the KV100 were equal, the HTHS of the 10w-30 would be higher than the 5w-30.

Amsoil SS 5w-30 ---- KV100 = 10.3 cSt, HTHS = 3.11 cP
Amsoil SS 10w-30 --- KV100 = 10.0 cSt, HTHS = 3.11 cP

Same deal.

Amsoil SS MaxDuty Diesel 5w-30 ---- KV100 = 12.0 cSt, HTHS = 3.5 cP
Amsoil SS MaxDuty Diesel 10w-30 --- KV100 = 12.1 cSt, HTHS = 3.5 cP

Those 2 are pretty much the same, but it's also a boutique diesel oil using pretty stout base oils in order for both to reach the 3.5 cP HTHS.

Your initial post only mentioned hths so that's what I responded to.

 

[Rytautas]

In general and also after being on bitog for a while, I have concluded that best is to move up a viscosity grade from what manufacturers specify. i.e. If the owner's manual specifies or recommends xWy, I would use xW(y+10). unless y is 50 or higher.

I would also adjust the x based on the ambient temp and not what the OM says.

since I don't own any xW8 or xW16 cars, that rule still applies.

The above rule applies only to US. I am not sure but i think European OM & recommendations are more on target.

Interesting