Oil weight for 5.3? 0-20 no good?

[viven44]

Here is a viscosity/flow demo on 10W-40 that I shot recently after replacing the valve stem seals on an old BBF

30 secs after cold start --- not much flow.. clearly the bearings and other components are designed to handle this 'sludge' for a little while

Watch Oil flow cold 30 secs | Streamable

Watch "Oil flow cold 30 secs" on Streamable.

streamable.com

Close to fully hot --- what a difference

Watch Oil flow fully hot | Streamable

Watch "Oil flow fully hot" on Streamable.

streamable.com

 

[Z15]

LOL, you know that the oil pumps are positive displacement right?

Positive displacement, meaning that for one revolution they pump the same volume of fluid regardless. Your graph above is only true for rotodynamic style pumps and totally not applicable to a forced oil lubrication system that uses a positive displacement pump.
...

So in your opinion thicker liquid flows just as fast as thin liquid?

 

[vcode]

So in your opinion thicker liquid flows just as fast as thin liquid?

Thickness and viscosity are related, but only viscosity is definable. It is the resistance to flow. Generally speaking, a thicker liquid will not flow as fast as a thinner one on its own. Put it in a PD pump and it will flow the same per revolution, but the more viscous fluid will require more energy to do so.

 

[Scarey]

Thickness and viscosity are related, but only viscosity is definable. It is the resistance to flow. Generally speaking, a thicker liquid will not flow as fast as a thinner one on its own. Put it in a PD pump and it will flow the same per revolution, but the more viscous fluid will require more energy to do so.

And that’s probably why gm went to 0-20. Take less energy to pump meaning better mpg. I think the evidence is pretty clear 20wt for mpg and 40 for engine longevity. Not saying this is cause of latest mess, just an observation.

 

[vcode]

And that’s probably why gm went to 0-20. Take less energy to pump meaning better mpg. I think the evidence is pretty clear 20wt for mpg and 40 for engine longevity. Not saying this is cause of latest mess, just an observation.

Well I'd like to see evidence of any kind that actually quantifies if/how much better 40 is for longevity. Lots of speculation. There are millions of non-GM vehicles out there running 0W20 for over a decade without issues.

 

[GMCChevy]

Well I'd like to see evidence of any kind that actually quantifies if/how much better 40 is for longevity. Lots of speculation. There are millions of non-GM vehicles out there running 0W20 for over a decade without issues.

Even GM vehicles.

 

[viven44]

Found this bulletin from 2013, it sure looks like GM made a big push for 0W-20 back then for 2014 year models

https://static.nhtsa.gov/odi/tsbs/2013/MC-10246634-9999.pdf

saying that apparently

"These engines utilize an advanced combustion system that maximizes the potential of the direct injection (DI) fuel system, active fuel management (AFM), variable valve timing (VVT), two stage oil pumps and other technologies. The dexos1™ 0W20 oil supports these technologies"

but they sure have walked back in the face of the recall and saying 0W-40 is better in the suspect engines (I doubt they have volume reliability data to back that up, this doing so must fundamentally suggest that they believe 0W-40 is better on the 6.2L and has the best chance of taking those engines to the "finish line" despite the use of all these awesome fuel savings technologies like DFM, DI)

More from the bulletin.
Question: Can another oil such as 5W30 that is cheaper and more widely available be used in place of dexos1™ 0W20oil?

Answer: No. The 5.3L and 6.2LV8 EcoTec3 engines available in the 2014 Silverado 1500 and Sierra 1500 pickup trucks were designed, engineered and validated to run using dexos1™ 0W20 oil. This is the ONLYoil approved for these engines.

Needing more comparative data will take years and unfortunately not be possible if everyone keeps using 0W-20. All we know is the GMT800/900 engines easily went to 300K on 5W-30. How many 200K engines have we seen here on 2015+ year models ? It’s gonna take more years to see how reliable these are. Our 2018 Tahoe sure started having some problems around the 90K mark.. oil burning, intermittent blinking misfire CELs after long trips, etc

 

[Scarey]

The oil geek makes a pretty compelling argument for oil a little thicker than 20.

 

[GMCChevy]

Found this bulletin from 2013, it sure looks like GM made a big push for 0W-20 back then for 2014 year models

https://static.nhtsa.gov/odi/tsbs/2013/MC-10246634-9999.pdf

saying that apparently

"These engines utilize an advanced combustion system that maximizes the potential of the direct injection (DI) fuel system, active fuel management (AFM), variable valve timing (VVT), two stage oil pumps and other technologies. The dexos1™ 0W20 oil supports these technologies"

but they sure have walked back in the face of the recall and saying 0W-40 is better in the suspect engines (I doubt they have volume reliability data to back that up, this doing so must fundamentally suggest that they believe 0W-40 is better on the 6.2L and has the best chance of taking those engines to the "finish line" despite the use of all these awesome fuel savings technologies like DFM, DI)

More from the bulletin.
Question: Can another oil such as 5W30 that is cheaper and more widely available be used in place of dexos1™ 0W20oil?

Answer: No. The 5.3L and 6.2LV8 EcoTec3 engines available in the 2014 Silverado 1500 and Sierra 1500 pickup trucks were designed, engineered and validated to run using dexos1™ 0W20 oil. This is the ONLYoil approved for these engines.

Needing more comparative data will take years and unfortunately not be possible if everyone keeps using 0W-20. All we know is the GMT800/900 engines easily went to 300K on 5W-30. How many 200K engines have we seen here on 2015+ year models ? It’s gonna take more years to see how reliable these are. Our 2018 Tahoe sure started having some problems around the 90K mark.. oil burning, intermittent blinking misfire CELs after long trips, etc

2014 was 11 years ago it shouldn't be that hard to find work trucks or even regular drivers with 200k+ on them. I think there are some members floating around the forum who posted mileage up there in some of the reliability anf mileage posts.

 

[viven44]

2014 was 11 years ago it shouldn't be that hard to find work trucks or even regular drivers with 200k+ on them. I think there are some members floating around the forum who posted mileage up there in some of the reliability anf mileage posts.

No, I just checked an auction I have membership at; there are plenty of 200K+ mile trucks listed there 2014 and newer with very few having mechanical faults so I have no doubts the 0W-20 can take it past 200K..... interestingly 5.3L to 6.2L showing up at a 25:1 ratio for 200K+ mile ones, and at a 12:1 ratio for <100K mile ones....