Hopefully not a thick vs. thin thread

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Ok, I know everyone hate the thick vs. thin threads unless you are the guy that puts 20w50 in everything.
Just bear with me, this may be a lot.

I've done a lot of research and reading, including this forum, about thick vs. thin, and wanted some input.
My goal is simple, minimize start-up wear without throwing away high temp performance and shear stability. If shear and VII breakdown wasn't a problem, I'm sure everything would be a 0w40 or 0w50 and case is closed but that's not the case. Part of why the thick vs. thin is so debated.

So, I would like to start with that my truck just had the motor rebuilt, going to take care of it under warrantee and just run 5w30 supertech full syn in it for 3000 intervals until my warrantee is up. After that, I would like to start experimenting with different weights and doing UOAs with them and let the numbers do the talking.
Until then, I'd like to hear different peoples input. This truck calls for anything from 5w30 to 20w50 based on ambient temperature. I'm all about start-up lubrication but don't want to sacrifice on shear stability or high temp performance (for reference, I live in Florida).
At the same time, I'd like to know what really makes a bigger difference. If I chose a 0W40, that would seem to cover a good range for cold start pumpability and high temperature. Also, I'd like to make it known that I'm aware that in a hotter area like mine, that cold start-ability may seem pointless or overkill, however, I know that the thicker the base oils weight is, the higher up on the graph it goes towards 0 degrees. Even though the lines get closer, a 0w will always stay thinner than a 5w as it warms up, including around ambient temps like 70-90 degrees, until it reaches operating temperature. This may be splitting hairs a bit but, hey, if the wear numbers are lower, I'll run with it. Theoretically, as long as the operating viscosity is the same, then wear should be decreased the lower the base weight is (not accounting for HTHS with higher VIIs) regardless of ambient temperature. Even if its 100 degrees outside, the 0w40 will be thinner at startup compared to a 5w40 or 10w40, even if it's not significant.
Now, all of this of course depends on the engine, which mine is a basic sohc 3.0l V6 with a timing belt (no chain to shear the oil more)
My thought process because of this leads me to believe that I should have lower wear numbers running something like 0w40 in it over 5w40 or 10w40, since the oil shouldn't shear much anyway (correct me if I'm wrong) because of the engine I have and because of the better cold flow performance. Also not overly worried about shear since I will be doing short OCIs (3k-5K). Price of oil doesn't really matter to me, considering I run Tribodyn in my Toyota Venza with 8k OCIs. I like to drive this truck hard so I want to make sure that if I ran something like 0w40, that the shear stability wouldn't increase wear when the engine is hot, which would ruin the point of the very small gain in cold start performance I would get over a 5w40. Again, splitting hairs, I know. But I figured this could spark a more in-depth debate regarding thick vs. thin. Maybe a 0w30 would be better, Idk.
I'd like to clarify that any of these oils I'm referring to would be full synthetic, preferably PAO and/or ester based like maybe LiquiMoly or Redline, so the VIIs should be more stable, from what I know.

SO, with this massive post out of the way, what do you guys think?
 
I doubt the viscosity of oil would matter much unless the oil was too thick for below freezing starts or you ran the engine hard towing heavy trailers If the rebuild was quality and stock clearances a 0 or 5W-30 or 40 using any of the major brands oil with the proper ratings would be fine. Take a breath cause you are chasing your tail with all the ideas you posted.
 
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IMHO, if a Euro 0W-40 is good enough for AMG, Porsche, SRT, the GT-R and the 24hr cars at Sebring, it's probably good enough for your Nissan ;)

Also, you can usually find M1 0W-40 or Castrol 0W-40 on sale. If you want something a bit more exotic, I'd take a look at the @High Performance Lubricants selection of Euro and Super Car oils.
 
Is that Tribodyn the ceramic based oil?
Yes. It is the first motor oil to receive a patent in many years apparently. The ceramic additive is supposed to cling to hot parts to essentially create a coating that fills in gaps and coat high stress parts like cam lobes to the point that it can nearly eliminate engine wear. They claim it can completely stop engine wear under certain circumstances, however, I've seen a UOA that did have some wear. Of course it supposedly will get better with continuous use. I haven't seen much anywhere regarding it other than all these people like in Nascar or whatever that use it but only like 1 or 2 UOAs so I figured I'd test it out myself long term and see how it goes.
 
I doubt the viscosity of oil would matter much unless the oil was too thick for below freezing starts or you ran the engine hard towing heavy trailers If the rebuild was quality and stock clearances a 0 or 5W-30 or 40 using any of the major brands oil with the proper ratings would be fine. Take a breath cause you are chasing your tail with all the ideas you posted.
I'm convinced my brain is designed to overthink everything lol. I'm excited to do UOAs with different oils later on to see if any of my theories are true.
 
IMHO, if a Euro 0W-40 is good enough for AMG, Porsche, SRT, the GT-R and the 24hr cars at Sebring, it's probably good enough for your Nissan ;)

Also, you can usually find M1 0W-40 or Castrol 0W-40 on sale. If you want something a bit more exotic, I'd take a look at the @High Performance Lubricants selection of Euro and Super Car oils.
Thank you, I think after the warrantee period, I'll start with 0w40 and go from there. Most likely Castrol or LiquiMoly.
 
My goal is simple, minimize start-up wear without throwing away high temp performance and shear stability.
10W30, 15W40 and 20W50 in descending order have the best response to VIIs and generally require lower amounts compared to other viscosity grades. Not always the case, but as you draw a pattern of HTFS, you will get the point.


Theoretically, as long as the operating viscosity is the same, then wear should be decreased the lower the base weight is (not accounting for HTHS with higher VIIs) regardless of ambient temperature.
Again. VIIs do not upscale neither hydrodynamic protection nor film strength. It just affects the flow rate at operating temperature. 0W50 won't protect better than 20W50 (Given both have the SAME ADDITIVES PACKAGE) which leaves hydrodynamic and mixed lubrication regime as the only variable contributing to the wear rate.
I like to drive this truck hard so I want to make sure that if I ran something like 0w40, that the shear stability wouldn't increase wear when the engine is hot, which would ruin the point of the very small gain in cold start performance I would get over a 5w40.
At this point AW and EP additives are in play that a thick vs thin argument. xW40 Euros like M1 FS are known to be pretty solid for your application. During extreme load such as towing or hard acceleration (different load from high speed driving), the situation leans more towards boundary lubrication regime.. Hello "addictives package".. See you later "thick vs thin". Viscosity becomes of little to no use.
Also not overly worried about shear since I will be doing short OCIs (3k-5K).

I'd like to clarify that any of these oils I'm referring to would be full synthetic, preferably PAO and/or ester based like maybe LiquiMoly or Redline, so the VIIs should be more stable, from what I know
PAO is not meant to protect better, it is meant to last longer and maintain performance throughout the OCI. If you are going to do 3k to 5k OCIs, that's a waste of money. And a poorly formulated PAO/Ester base will often produce not so welcome outcomes in terms of wear protection becauses esters are very polar and will compete with AW and EP additives for contact sites. Not a problem with well thought out formulas like seen in M1. Hope that helps.
 
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Perhaps you should message an administrator and ask that the title of this thread be changed to reflect the topic you wish to discuss rather than lead into the topic that you say you don't want to lead into.

What is your question exactly? About startup wear? Startup wear is way overblown here and elsewhere. Most wear does not occur at startup, the oil is thick then and provides adequate film thickness. Most wear occurs during warmup. But severe wear can happen during operation if the HT/HS is inadequate. That's really the parameter that is most important for wear, not the winter rating of the oil. As long as the winter rating is appropriate for the expected starting temperature then it becomes largely irrelevant after that.

I'm not sure where the random reference to Tribodyn plays here however.
 
You are in Florida and if it can run just about any oil spec like you said, I would not worry about the cold start rates. Any 0/5w40, 10w30, 10w40 or a 5w30 Euro would suit that engine fine. If going 5w30 I would pick the PP Euro L 5w30 over the Supertech Syn as it has high HTHS and is just a couple bucks more. Given you are only running 3k oci, I would just run QS blend as it is pretty cheap at Walmart or go on Grainger.com and order a 6gal box of Duramax oil for about $45 +/- and get a 10w30 Semi syn or the Conv- which is a blend HM and run it. Don't think there is a 10w30 syn on there site but they do have a 5w30 syn if you really wanted or had to run 5w30 for warranty, if still available.
 
[EDIA=googlesheets]1oIYJP_5lgdt9l-_5n_ftKL5ScaaeY0MErFRothajZos[/MEDI]

New here... Is there a discussion/explanation of all the columns in that table and their practical application? Just curious to know more. Thanks
 

I bet you'll find this discussion enlightening.
 

I bet you'll find this discussion enlightening.
Indeed... And overwhelming. o_O😂 I guess I'll stick with whatever is on sale.
 
Ok, I know everyone hate the thick vs. thin threads unless you are the guy that puts 20w50 in everything.
Just bear with me, this may be a lot.

I've done a lot of research and reading, including this forum, about thick vs. thin, and wanted some input.
My goal is simple, minimize start-up wear without throwing away high temp performance and shear stability. If shear and VII breakdown wasn't a problem, I'm sure everything would be a 0w40 or 0w50 and case is closed but that's not the case. Part of why the thick vs. thin is so debated.

So, I would like to start with that my truck just had the motor rebuilt, going to take care of it under warrantee and just run 5w30 supertech full syn in it for 3000 intervals until my warrantee is up. After that, I would like to start experimenting with different weights and doing UOAs with them and let the numbers do the talking.
Until then, I'd like to hear different peoples input. This truck calls for anything from 5w30 to 20w50 based on ambient temperature. I'm all about start-up lubrication but don't want to sacrifice on shear stability or high temp performance (for reference, I live in Florida).
At the same time, I'd like to know what really makes a bigger difference. If I chose a 0W40, that would seem to cover a good range for cold start pumpability and high temperature. Also, I'd like to make it known that I'm aware that in a hotter area like mine, that cold start-ability may seem pointless or overkill, however, I know that the thicker the base oils weight is, the higher up on the graph it goes towards 0 degrees. Even though the lines get closer, a 0w will always stay thinner than a 5w as it warms up, including around ambient temps like 70-90 degrees, until it reaches operating temperature. This may be splitting hairs a bit but, hey, if the wear numbers are lower, I'll run with it. Theoretically, as long as the operating viscosity is the same, then wear should be decreased the lower the base weight is (not accounting for HTHS with higher VIIs) regardless of ambient temperature. Even if its 100 degrees outside, the 0w40 will be thinner at startup compared to a 5w40 or 10w40, even if it's not significant.
Now, all of this of course depends on the engine, which mine is a basic sohc 3.0l V6 with a timing belt (no chain to shear the oil more)
My thought process because of this leads me to believe that I should have lower wear numbers running something like 0w40 in it over 5w40 or 10w40, since the oil shouldn't shear much anyway (correct me if I'm wrong) because of the engine I have and because of the better cold flow performance. Also not overly worried about shear since I will be doing short OCIs (3k-5K). Price of oil doesn't really matter to me, considering I run Tribodyn in my Toyota Venza with 8k OCIs. I like to drive this truck hard so I want to make sure that if I ran something like 0w40, that the shear stability wouldn't increase wear when the engine is hot, which would ruin the point of the very small gain in cold start performance I would get over a 5w40. Again, splitting hairs, I know. But I figured this could spark a more in-depth debate regarding thick vs. thin. Maybe a 0w30 would be better, Idk.
I'd like to clarify that any of these oils I'm referring to would be full synthetic, preferably PAO and/or ester based like maybe LiquiMoly or Redline, so the VIIs should be more stable, from what I know.

SO, with this massive post out of the way, what do you guys think?
Probably 20W-50 until the engine is broken in (the first 10,000 miles) so that you don't need another rebuild. Then, switch to 15W-40 if you like. You don't need 0W-40 in Florida. If this engine has a tendency to wear out and you drive hard as you said, 0W-40 is like water in comparison to 15W-40 and won't protect anywhere near it. The VII temporarily shears in the valvetrain and a SAE 0W-40 protects nowhere like a SAE 40 but a good, stout 15W-40 with little VII comes closer to a SAE 40, for which ideally HTFS = HTHS, where HTFS is measured at full shear (like in the valvetrain) and HTHS is measured at high shear.

See my HTFS table. For example, M1 FS 0W-40 has HTFS = 2.3 cP but Mobil Delvac 15W-40 and Mobil Delvac Extreme 15W-40 have HTFS = 3.2 cP. The minimum HTHS value for SAE 0W-40 and 15W-40 are 3.5 cP and 3.7 cP, respectively. The HTFS value for M1 FS 0W-40 is nowhere close.

Estimated HTFS and VII content of selected oils
 
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