0w20 for heavy driving?

I starting using 5w30 to try and get consumption down in my Mazda. Made no difference but I still use it as the rest of my cars use it
 
All the people saying you'll have less wear with thicker oil need to show some comparative oil analysis data to prove it. This nonsense reminds me of the people in the 1990's who thought 5w-30 was gonna cause the end of the world.

Run 0w-20 year round and forget it.
 
page 6-27

https://cdn.mazda.ca/common/en/pdf/...32050342.1583610575-294194473.1583610575

Except U.S.A., Canada
SKYACTIV-G 2.0, SKYACTIV-G 2.5
Use SAE 5W-30 engine oil.

page 6-28

SKYACTIV-G 2.0, SKYACTIV-G 2.5
Use SAE 5W-30 engine oil. If SAE 5W-30
engine oil is not available, use SAE 5W-20
engine oil.
The quality designation SM or SN, or
ILSAC must be on the label.
SKYACTIV-G 2.5T
Use SAE 5W-30 engine oil. If SAE 5W-30
engine oil is not available, use SAE 0W-30
or SAE 10W-30 engine oil.
The quality designation SM or SN, or
ILSAC must be on the label.
 
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Used oil analysis is proven to determine the serviceability of a lubricant.
It is not proven to determine wear control, or even detect all wear. It may detect certain mechanical issues with known wear markers.
When you have a hammer everything looks like a nail. I Would not give a uoa wear metals analysis the same weight as a tear down and micro-metering/weighing of parts.
UOAs May look like science..but they are limited in usefulness even with more sophisticated analysis interpretation,

That said, we can all agree that higher oil film thickness provides lower wear.
 
Originally Posted by Bryanccfshr
Used oil analysis is proven to determine the serviceability of a lubricant.
It is not proven to determine wear control, or even detect all wear. It may detect certain mechanical issues with known wear markers.
When you have a hammer everything looks like a nail. I Would not give a uoa wear metals analysis the same weight as a tear down and micro-metering/weighing of parts.
UOAs May look like science..but they are limited in usefulness even with more sophisticated analysis interpretation,

That said, we can all agree that higher oil film thickness provides lower wear.


If we go by what you say, there should be some data out there of actual tear downs of the same engines used in the same conditions with higher wear using 0w-20 as compared to other oils.

Again, the same exact things were heard 25 years ago about 5w-30 motor oil causing more wear than 10w-30 or 10w-40. Back then, again, I never saw anyone submit data that proved higher wear in engines that used 5w-30.

If I see data proving that it does in fact cause higher wear I'll even stop running 0w-20 in my Tundra.
 
Think of oil thickness as a risk mitigation margin when things are not perfect and gentle.
As long as everything is running well that barrier of protection seems like it isn't doing anything.

I have 0w20 in the 4 runner and more in my cabinet for a later change along with 10w30, 5w30 and 0w40. So I am not dogmatic about this, I am just realistic on the effect-cause relationship of internal engine wear and damage. And use the appropriate viscosity based on the season and the intended service during the OCI.

Effect =moving parts touch and cause = failure of the oil film to separate the parts.
 
[Linked Image from 3.bp.blogspot.com]
 
Originally Posted by PowerSurge
If I see data proving that it does in fact cause higher wear I'll even stop running 0w-20 in my Tundra.


There have been lots of thread discussions in this forum with links to engine wear studies showing that higher viscosity can lower wear. You can find all kinds of technical studies with a Google search.

And obviously, if an engine isn't pushed hard then a lower viscosity will still do it's job. It's when the oil temperature gets higher than "normal" is when thinner oil loses film thickness, and more wear can occur. Seems to be a bigger wear increase when gettig down into the xW-16 viscosity range. xW-20 will work for most, but going xW-30 adds some insurance to maintain an adequate oil film thickness between parts for increased temperature, fuel dillution and shearing.
 
Originally Posted by PowerSurge
All the people saying you'll have less wear with thicker oil need to show some comparative oil analysis data to prove it.


A thicker oil just reduces the probability of a wear event in the engine, it's not a guarantee of less wear in all cases. Once the metal parts are separated in hydrodynamic lubrication, job done. A thicker oil just keeps them further apart, if you think you need it for a higher stress application. The cost is more viscous drag and so a very slight hit to fuel economy.

From member Tundraotto in a previous thread, they posted a good article LINK

Quote
Cyril Migdal, head of global application technology for lubricant additives at the chemical maker Lanxess. "When there is less film thickness, there is a higher probability that engine parts can come into contact with each other. If they come into contact, you will have wear."


Quote
fuel efficiency benefit comes with lower viscosity ....... a change from a 10W-40 to a 0W-20 oil, assuming identical engines, could bring up to a 3% improvement, he estimates.


It's freedom of choice, on a spectrum of: cost (fuel consumption) Vs risk (wear probability).


Ref:
https://cen.acs.org/business/specialty-chemicals/Engine-oil-becomes-critical-automakers/97/i5
 
Originally Posted by SR5
Originally Posted by PowerSurge
All the people saying you'll have less wear with thicker oil need to show some comparative oil analysis data to prove it.


A thicker oil just reduces the probability of a wear event in the engine, it's not a guarantee of less wear in all cases. Once the metal parts are separated in hydrodynamic lubrication, job done. A thicker oil just keeps them further apart, if you think you need it for a higher stress application. The cost is more viscous drag and so a very slight hit to fuel economy.

From member Tundraotto in a previous thread, they posted a good article LINK

Quote
Cyril Migdal, head of global application technology for lubricant additives at the chemical maker Lanxess. "When there is less film thickness, there is a higher probability that engine parts can come into contact with each other. If they come into contact, you will have wear."


Quote
fuel efficiency benefit comes with lower viscosity ....... a change from a 10W-40 to a 0W-20 oil, assuming identical engines, could bring up to a 3% improvement, he estimates.


It's freedom of choice, on a spectrum of: cost (fuel consumption) Vs risk (wear probability).


Ref:
https://cen.acs.org/business/specialty-chemicals/Engine-oil-becomes-critical-automakers/97/i5


Those words are great, but where are the tear down comparisons showing the ‘higher wear'. It's one thing to say "higher wear probability" and "if" they come in contact you will have wear. Let's see the tear downs. Your oil has anti-wear additives to compensate.

Engines operate with oil pressure. The parts are getting a constant stream of oil flow.
 
Originally Posted by PowerSurge
Engines operate with oil pressure. The parts are getting a constant stream of oil flow.


Yes, oil pressure only means oil is flowing. Oil pressure really doesn't add to the effectiveness of oil viscosity in terms of the produced oil film thickness. Oil viscosity does matter when talking about minimum oil film thickness between parts, which has a large effect on keeping moving parts from contacting each other.
 
Originally Posted by Mike L. V.
Plenty of cars use 0W-20 for all conditions. Use it with ease.


Of course for most the motoring public in the USA, yet you are missing the nuance and nature of the discussion by not seeking a deeper understanding of MOFT.
 
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Originally Posted by Bryanccfshr
Originally Posted by Mike L. V.
Plenty of cars use 0W-20 for all conditions. Use it with ease.


Of course for most the motoring public in the USA, yet you are missing the nuance and nature of the discussion by not seeking a deeper understanding of MOFT.




It's a Mazda not a drag car. There are plenty of GMs, Hondas, and Toyotas that use 0W-20 without issue. My opinion...it doesn't matter. It's an econo box and it will do just fine with 0W-20. Passing cars and frequent downshifting is nothing out of the ordinary. Use 0W-20 and sleep easy. It's motor oil not a 401K.
 
Originally Posted by PowerSurge

but where are the tear down comparisons showing the ‘higher wear'. It's one thing to say "higher wear probability" and "if" they come in contact you will have wear. Let's see the tear downs.


I'm not here to do your homework for you, it's been known for decades with lots of SAE papers published with real measured wear data. HTHS viscosity is the important parameter here as the primary line of defence with add packages being the secondary line of defence.

This is a good thread to get you started, with real SAE data provided
https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4836029/1

After that Google is your friend.

BTW I'm not telling anyone what to to, just saying it's an obvious spectrum of Cost Vs Risk. Find your happy zone and chill. I've started running thinner oils than before as I began to realise how low my wear risk was driving a family 4-cylinder wagon to drop my kids at school.
 
I think that there are too many variables to make a blanket statement like this. If you engine lasts 200,000 miles on 0w20 would it have made it to 220,000 with 5w30?

We just don't know yet the argument continues.
 
Originally Posted by Skippy722
This site turned me into a "thickie" so I curse all of you. I used to just grab a few jugs of Valvoline till I started coming here!
...

Funny, this site got me to trust "thin" oils.

I was concerned when I got my '05 Grand Caravan with the 3.8 that spec'ed 5w-20, but just a few years before was a 5w-30 motor with no internal changes.
After a few changes with 5w-20 and running a summer trip over 1000 miles in 100°F+ heat at highway speeds and having a spectacular UOA (yes, I know they don't show everything), I was satisfied that it was safe to use whatever oil is spec'ed for the engine.

I also know that you can usually go up or down a grade and still be safe on most vehicles as well.
 
Originally Posted by wolf_06
Hey folks,

My skyactiv 2.0 L requires 0w20 of any brand really. It also says that a 30 weight is acceptable for warmer climate.

I drive pretty heavy, passing cars on highway, downshift many times, high revving, etc.

Would a 5w30 or in this case a 0w30 would give me a better protection for long term? or its just splitting hair and a 0w20 is fine to take the abuse?

I do 80% highway, 600 km per week, my OCI is 8000 km recommended by Mazda.

Any inputs is appreciated!

0W-20 is the recommended oil for most new BMWs and Audis driven on the autobahns at 140 mph now. You're talking about a Mazda driven on Canadian roads. So...
 
Originally Posted by blupupher
Originally Posted by Skippy722
This site turned me into a "thickie" so I curse all of you. I used to just grab a few jugs of Valvoline till I started coming here!
...

Funny, this site got me to trust "thin" oils.


Same here, this site has turned me from super thick (Edge 10W60, M1 5/15W50, Penrite 20W60) to thin(ish). With the simple realisation that my car engine would out last my car body regardless of the oil I used, given regular oil changes.

Then it turned me cheap, and I now just chase what is on sale. Which are mostly 30 and 40 grades in Australia. The last oil I purchased was thinner than what my owners manual said to use, but I know it will be fine for my mundane application.
 
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