Oil weight for 5.3? 0-20 no good?

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Antonm

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. GM is only using 0W40 on recalled motors.

Not true.
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The rotating assembly (aka all the oil lubricated components) are identical, part number for part number, between the Camaro/ Corvette/ Cadillac 6.2 and the Tahoe 6.2.

Yet even without manufacturing defects , GM recommends 0W40 in those identical rotating assembly engines. Why you ask,,, oh that's easy, because the CAFE standard hit isn't near as big for those because GM sell so many less of them.

So there 0W20 oil guy, please tell me what 0W20 oil does better than 0W40 oil.

Its slightly cheaper sure, but there is not a single environment or operating condition where an 0W20 oil protects the engine better than an 0W40 oil does, not a single one.
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jfoj

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Again, show me all the oiling issues with 5.3L's produced since 2013. Heck, include 6.2L's as well that are not affected by the recall due to improperly machined parts. Your world and the real world are light years apart. Nobody is going to spend $500 or more every other oil change to get their transmission fluid changed.
@vcode,

You CLEARLY do not understand and I doubt any effort to educate you would open your eyes.

The prior generation trucks with these engines had either 6 or 8 speed transmissions, different number of overdrive gears and the TCM (Transmission Control Modules) were configured way differently. Even the TCM in the L84 is very differently configured than the L87. Additionally I believe many of the earlier engines had coated main and connecting rod bearings, but it appears for some reason that GM phased out the coated rod bearings over the past 5+ years, really stupid decision on their part. Probably to save $1 per engine??

A few things you need to understand.

1. Yes the L87 has clearly some problems, are they really manufacturing problems, or are they really ECM/TCM configuration problems along with the fact they no longer use coated connecting rod bearings and are running 0W20 oil when the L87 is lugging down the highway at 1200-1500 RPM and rarely ever shifts below 9th gear which is the 2nd Over Drive ratio in the 10 speed. The L87 is a heavily loaded engine on the highway. The L84 is a much different beast, no 2 stage oil pump, it is running higher oil pressure full time than than the L87 and the L87 vehicles also have a TCM that downshifts to 7th or 8th gear without much load on the engine, the L87 will downshift to 9th gear, but not often will drop below 9th gear unless the engine loading is approaching 90+%.

2. Taking the possibly manufacturing and/or configuration problems out of the picture you still are dealing with very high bearing loading on the current L87 platforms. 0W40 can handle far more bearing loading and offers better cushioning than 0W20. 0W20 has almost no safety margin in the 6.2l engines. Will it work, sure under some more ideal conditions, if you rarely drive your L87 on the highway or tow with it, 0W20 is probably fine, but again no margin. Add a bit of fuel dilution into the oil, good luck.

3. Taking all the early failures away from the L87, you still have high pressures on the rod bearings while cruising on the highway, way more than the 5.3l as the 5.3l does not have the torque output and the TCM downshifts far quicker and more gears than the 6.2l.

4. Then you have the valvetrain parts, tiny needle bearings in the lifters that do not do well with contamination and fuel diluted oil.

5. 0W20, 0W16 and 0W8 was not formulated for long term engine protection, it was formulated in an attempt to squeeze a very small increase in fuel economy out of the engines to help the manufacturer with CAFE requirements. Sure some vehicle/engine combinations have survived on these oils, but for higher power, heavier vehicles this is not a wise choice, but the owners did not get to make the choice the manufacturers forced it down our throats, just like many other things we really do not want or need.

Load your vehicle up with the Koolaid, run the oil until the OLM hits 0% or claim you are smarter than everyone and you can run the oil to 15,000 miles or more. Have fun and see how it works out for you.

Not sure where you are getting $500 oil changes figures from. I guess if you only use the dealership, but even then you are talking crazy numbers. I do all my own work, unlike many here that grumble and argue about things then take their vehicle to the dealership.

My oil changes cost me $75 at this point and if I drain and fill 7 quarts from my transmission, higher number of quarts due to the larger aftermarket trans pan, it costs me $47. So an oil change and trans drain and fill costs me $122.

I look at this as money and time well invested, oil is cheaper than metal as the saying goes. I would rather over maintain my vehicle because there is no way I could perform any internal engine or transmission repair for the extra money I will spend on maintenance.

I have 2 neighbors with 2025 6.2l that are NOT running 0W20 in their engines, both had first oil changes well before 1000 miles, they plan on aggressively maintaining their investment.

You do you, run the Koolaid in your engine, I will do what I feel is correct and I share what I do so others may learn and decide for themselves how they may maintain their vehicles.
 
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Silverado4x4

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Humm I guess my neighbor got a special GM 5.3 in his 2020 as he has over 130,000 miles on his 5.3 mostly highway and changes his oil when the OLM tells him to all on 0W20.
 

Antonm

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Humm I guess my neighbor got a special GM 5.3 in his 2020 as he has over 130,000 miles on his 5.3 mostly highway and changes his oil when the OLM tells him to all on 0W20.

Nothing special about it, just means that for his use case the 0W20 is adequate.

The 0W20 oil isn't "bad" or anything, the point is the 0W40 oil is better in every regard and has no downside compared to the 0W20 oil other that it costing slightly more.

Here's an easy to understand analogy. Lets say you have a jet ski trailer you need to tow. You go down to the local auto parts store and there are two inch hitch balls with weight ratings from 3,500 to 12,000 pounds on the shelf.

The jet ski trailer is light, you grab the 3,500 pound rated ball and go. It's perfectly adequate and will work just fine if that jet ski trailer is all you ever tow.

But, would there be any downside (other than it costing slightly more) to picking the 12,000 pound rated hitch ball of the same size? Would there ever be a situation where the 3,500 pound ball did a better job than the 12,000 pound rated one? Nope, sure wouldn't be, and it would give you a larger safety margin when towing that jet ski trailer.

And should some situation outside of the normal happen that places more stress of the hitch ball (like you decide to help a friend out and pull his boat out of the water for him), you'd have a margin before a failure occurred and wouldn't be overstressing your barely adequate for your normal usage hitch.

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