Pa winters

[JAG]

Originally Posted By: dnewton3
There is no data that shows any difference between a 15w40, 10w30, or 5w-40 when it comes to wear; they all wear about the same. Check my Dmax UOAs with dino 10w30 and those running thicker grades, even with syn. They are ALL normal in wear.


To correctly state that there is no such data would require you to be aware of ALL data related to that. Nobody is aware of all such data. This is obvious when considered so perhaps your intent was to say that you are not aware of any data that shows any difference between a 15w40, 10w30, or 5w-40 when it comes to wear.

 

[skyship]

Originally Posted By: JAG
Originally Posted By: dnewton3
There is no data that shows any difference between a 15w40, 10w30, or 5w-40 when it comes to wear; they all wear about the same. Check my Dmax UOAs with dino 10w30 and those running thicker grades, even with syn. They are ALL normal in wear.


To correctly state that there is no such data would require you to be aware of ALL data related to that. Nobody is aware of all such data. This is obvious when considered so perhaps your intent was to say that you are not aware of any data that shows any difference between a 15w40, 10w30, or 5w-40 when it comes to wear.


DNewton is correct to say that there is no difference in cold start wear between an 0/40 and an 15w40, as I took a look at that research myself. I would point out that there is no real difference if you use the oil within the recommended temperature range for the grade, so if you use a 15w40 below the minus 5C quoted by most oil companies then it does result in slightly increased wear. There are a few studies showing a slight improvement with fully synthetic oils.

 

[bigjl]

Originally Posted By: JAG
Originally Posted By: dnewton3
There is no data that shows any difference between a 15w40, 10w30, or 5w-40 when it comes to wear; they all wear about the same. Check my Dmax UOAs with dino 10w30 and those running thicker grades, even with syn. They are ALL normal in wear.


To correctly state that there is no such data would require you to be aware of ALL data related to that. Nobody is aware of all such data. This is obvious when considered so perhaps your intent was to say that you are not aware of any data that shows any difference between a 15w40, 10w30, or 5w-40 when it comes to wear.


Wow, pedant......

 

[bigjl]

I have noticed that the wife's diesel Clio is slower to turn over with 10w40 in it, big mistake on my part putting it in as I had removed 0w40 Mobil 1 New Life with no more than 6k on it.

And the temps we are talking about in my case are only around 0 oC or -2oC, not the massively cold temps talked about in this thread.

If it got as cold as mentioned I suspect the Clio wouldn't turn over fast enough to actuay get going atall!

Volvo with low HTHS 5w30 starts as per usual, no difference whatsoever.

Makes sense to me that as dnewton says a lot of data suggests that no extra wear will occur with thicker oils (eg 15w40) but that due to being thicker when cold the biggest issue is not being able to start.

This is also the first time I have used a synth blend in the Clio, I recall I out in some semi synth a couple of years ago, leftover from a Taxi oil change aswell if memory serves, probably Chevron Supreme 10w40 semi.

This will be my last time putting anything other than full synth in the Clio. Will report back when I change it out next week if it is turning over faster on a cold start with its usual New Life in there.

 

[dnewton3]

Originally Posted By: JAG
Originally Posted By: dnewton3
There is no data that shows any difference between a 15w40, 10w30, or 5w-40 when it comes to wear; they all wear about the same. Check my Dmax UOAs with dino 10w30 and those running thicker grades, even with syn. They are ALL normal in wear.


To correctly state that there is no such data would require you to be aware of ALL data related to that. Nobody is aware of all such data. This is obvious when considered so perhaps your intent was to say that you are not aware of any data that shows any difference between a 15w40, 10w30, or 5w-40 when it comes to wear.



Allow me to be more specific.

Of all the data I've seen, collected and analyzed, including (nearly) 1000 UOAs for Dmax engines, from many regions around the globe (five of the seven continents), including just about every conceivable environment, use and driving condition utilizing many different lubes representing all manner of base stocks and viscosity ...
there is no statistically significant difference in wear data overall in regard to this topic because macro analysis shows this statement to be true. Micro analysis might be able to distinguish a "better" wearing lube, but it would only be applicable to that one situation, where macro analysis covers them all.

Do I have a copy of every single UOA ever done in a Dmax? No I don't. But then again, that is the beauty of statistical analysis; I don't need to have them all to use good mathematical methodology. This type of macro analysis modeling is used in nearly every mass product market around the world, including medicine, engineering, manufacturing, food production, etc. because it works and is proven true.

Forgive me for being short in my previous post.
Typically I'm chastised for being long-winded; having diarrhea of the keyboard so to speak.
Now it seems my brief statement above was too broad and general.
As it has been said, there is no pleasing all the folks all the time.

 

[JAG]

Thanks for clarifying, Dave. I wonder what studies have found on this matter. I probably have read some but time has erased any memory of them, if I ever came across any.

 

[dnewton3]

You can look at the 550 Duramax UOAs summarized in my article; that's a good place to start.