OCI, not when but why?

[diyer2]

Just use better oil, Amsoil would be my choice if you plan on keeping it longer than many.

https://www.amsoil.com/search/#q=0w20&t=totalProductsTab&sort=relevancy&numberOfResults=20

 

[Atlas]

17 hours ago, customboss said:

As if you didn’t know that. 

 

Had to keep the thread going, make sure it remains stirred. 

 

On a more serious note, one of these days I'll end up keeping a vehicle for the long haul. If I make it 100-150k that would be a first...boredom usually hits first. I've owned higher mileage vehicles, purchased or given to me and I generally prefer newer/nicer for my primary mode of transportation. But if I really like something I may end up keeping it.

 

0w20 in a diesel is still a little shocking to me. 5w30 in my first little diesel (GM 2.8) years back was also shocking, but those have held up over time. Can't say I'm not just a little skeptical of such thin oil in the 3.0 so I always like to hear perspective on it.

[customboss]

25 minutes ago, diyer2 said:

Just use better oil, Amsoil would be my choice if you plan on keeping it longer than many.

https://www.amsoil.com/search/#q=0w20&t=totalProductsTab&sort=relevancy&numberOfResults=20

 

Best bang for quality buck. 

[customboss]

12 minutes ago, Atlas said:

 

Had to keep the thread going, make sure it remains stirred. 

 

On a more serious note, one of these days I'll end up keeping a vehicle for the long haul. If I make it 100-150k that would be a first...boredom usually hits first. I've owned higher mileage vehicles, purchased or given to me and I generally prefer newer/nicer for my primary mode of transportation. But if I really like something I may end up keeping it.

 

0w20 in a diesel is still a little shocking to me. 5w30 in my first little diesel (GM 2.8) years back was also shocking, but those have held up over time. Can't say I'm not just a little skeptical of such thin oil in the 3.0 so I always like to hear perspective on it.

3.0 diesel was designed for 0w20 from ground up. 

Edited December 15, 2025 by customboss

[customboss]

11 hours ago, Grumpy Bear said:

And exactly what grave danger will befall the 3.0 with an increase in HTHS viscosity? Give me ya' all's best horror story. 

 

 

I want to hear TRUE SCIETIFICALLY VERIFIEABE experiences of 3.0 motors failing and traceable solely to higher HTHS viscosity. 

 

I already gave scholarly articles that PROVE it WILL reduce wear. The trade is fuel economy...sometimes. 

 

It was NOT designed for higher HTHS. You buy one and show us. Quit telling others what to do when you don’t have a risky dog in fight. You post what others tell you that support your bizzaro theories. 

[KARNUT]

38 minutes ago, Atlas said:

 

Had to keep the thread going, make sure it remains stirred. 

 

On a more serious note, one of these days I'll end up keeping a vehicle for the long haul. If I make it 100-150k that would be a first...boredom usually hits first. I've owned higher mileage vehicles, purchased or given to me and I generally prefer newer/nicer for my primary mode of transportation. But if I really like something I may end up keeping it.

 

0w20 in a diesel is still a little shocking to me. 5w30 in my first little diesel (GM 2.8) years back was also shocking, but those have held up over time. Can't say I'm not just a little skeptical of such thin oil in the 3.0 so I always like to hear perspective on it.

At 70 tomorrow. New or used and not collector cars. I’m usually good for 3 years with any daily driver. Something usually comes up. A kid needs a car or a good deal surfaces. Funny though the Odyssey will pass 3 years in February. 

[customboss]

On 12/15/2025 at 9:10 AM, KARNUT said:

At 70 tomorrow

Happy Birthday. 

[PunchT37]

Should we continue?

 

 

[customboss]

11 minutes ago, PunchT37 said:

Should we continue?

 

 

Or better said, GM engines need bandaids. 

[Black02Silverado]

10 hours ago, PunchT37 said:

Should we continue?

 

 

Interesting, If this was the case, every engine would be sitting at the dealership because it wouldn't provide protection. It's not the oil people!  It's the poor quality materials that manufactures are using all to save $$$$$$. 

I'm not just saying GM, every manufacture's engines that use 0w-20, 0w-16, and now 0w-8. 

[Grumpy Bear]

On 12/15/2025 at 9:40 AM, customboss said:

It was NOT designed for higher HTHS. You buy one and show us. Quit telling others what to do when you don’t have a risky dog in fight. You post what others tell you that support your bizzaro theories. 

 

So you have ZERO PROOF for  your whining ramblings that it is damaging to this motor. OMG what garbage. BTW, there is not such thing as "Designed for this HTHS". But even if it was, SAE 5W30 would not DAMAGE the motor. You are spouting half truths and drivel. And for very reason of physics demands, it will improve wear. You can't CANCEL STRIBECK.  do you think you are? God? 

 

Anyone else interested it the relationship between wear and viscosity hit this link

 

https://www.machinerylubrication.com/Read/518/motor-oils

 

[quote from link] 

The best protection against wear is probably a product that is a little thicker (such as SAE 10W-30 or 15W-40) and has more antiwear additives than the oils that support the warranty. The best oil for your vehicle depends on your driving habits, the age of your engine and the climate you drive in, but it is not necessarily the type of oil specified in the owner’s manual or stamped on the dipstick. [close quote}

 

0W20 isn't even available in the UK accord to FORD  and yet the 3.0 is. Yea, ground up design. 

 

 

 

Edited December 19, 2025 by Grumpy Bear

[customboss]

18 minutes ago, Grumpy Bear said:

0W20 isn't even available in the UK accord to FORD  and yet the 3.0 is. Yea, ground up design. 

We are talking about 3.0 GM turbo diesel and it’s not available in UK. 0w20 is sold in UK and EU quite readily. 
 

“ US-made GM 3.0L Duramax turbo diesel engine (such as the LM2 or LZ0 variants assembled in Flint, Michigan) is not available in new GM vehicles sold through official UK channels.”

 

God? Im just a Nasty Nasty man. Ask Stan.

[customboss]

@Grumpy Bear having actually worked on teams that designed engines we absolutely DO compute and test for MOFT for said engine design. IN ALL CONDITIONS. 
 

Its hard to be your age and be checked publicly but Im not Joshing’ ya. 

Edited December 19, 2025 by customboss

[Chuck FB]

On 12/14/2025 at 8:56 PM, Grumpy Bear said:

And exactly what grave danger will befall the 3.0 with an increase in HTHS viscosity? Give me ya' all's best horror story. 

 

 

I want to hear TRUE SCIETIFICALLY VERIFIEABE experiences of 3.0 motors failing and traceable solely to higher HTHS viscosity. 

 

I already gave scholarly articles that PROVE it WILL reduce wear. The trade is fuel economy...sometimes. 

 

 

This comment dives into what a youtube channel called DemonWorks who is a GM mechanic that works a lot on the 3.0 engine at his day job but also has owned numerous personal 3.0 trucks and he had done UOA with a variety of 0W-20 oil brands and then switched it up to a 5W-30 on his current truck and I believe he generated a couple of 5W-30 tests and so far there was certainly a statistical drop in wear metals. I think now he is trying a 0W-30 for the winter and so those UOA's are yet to be generated. One thing is for sure, it takes time to create UOA's with a daily driver and the odd long distance trip within that at times, there is no instant gratification "answer" like a person would desire as of course owners of the 3.0 intently watching his results want answers now so they can make a possible better oil choice now, not years from now and I can understand that. Collecting good quality long term data is not a five minute gratification process but that is a statement your more than well aware of !, its a statement I mention for others reading my post. 

[Grumpy Bear]

3 hours ago, Chuck FB said:

 

This comment dives into what a youtube channel called DemonWorks who is a GM mechanic that works a lot on the 3.0 engine at his day job but also has owned numerous personal 3.0 trucks and he had done UOA with a variety of 0W-20 oil brands and then switched it up to a 5W-30 on his current truck and I believe he generated a couple of 5W-30 tests and so far there was certainly a statistical drop in wear metals. I think now he is trying a 0W-30 for the winter and so those UOA's are yet to be generated. One thing is for sure, it takes time to create UOA's with a daily driver and the odd long distance trip within that at times, there is no instant gratification "answer" like a person would desire as of course owners of the 3.0 intently watching his results want answers now so they can make a possible better oil choice now, not years from now and I can understand that. Collecting good quality long term data is not a five minute gratification process but that is a statement your more than well aware of !, its a statement I mention for others reading my post. 

 

Exactly! 

 

I heard a really smart person the other day say, "Some peoples whisper is louder than a shout because of WHO they are not because of WHAT they say. Still doesn't make a lie the truth".

This Revelation isn't new to anyone who has invested any time in Stribeck, Hersey, Sommerfeld.