I have a 2022 Silverado with a 5.3L. My buddy has a 2026 GMC with a 6.2L. Every time I get my oil changed the specs are 20W Dextros synthetic. My buddy has been freaking out about the lifter thing he educated himself about after he bought the truck. I told him to make sure he gets his oil changed on schedule, and use synthetic. He has been reading online and watching videos (probably one!)* that the 20W which I use and his does also is too thin, it will hasten engine failure. Said he was going to have his changed to 30W, after initially considering 40W. I was like WTF, the factory specs are what they are. Nope, 20W is too thin. I just shake my head but thought I’d ask some of you fellas who are more engine-savvy than myself.
So, stick with the 20W or thicken it up to 30 or 40W?
*my buddy is a retired SF guy, in his early 70’s. He watches these “I have no fvcking idea where he finds them” videos about all kinds of stuff that makes you raise an eyebrow. Like Biden was dead the last two years he was in office and is buried in the Rose Garden, or there are military tribunals set up and a shitload of treason charges coming, or all the foreign-born members of Congress have been removed from office….yeah, THOSE kind of videos. So when he brought up the oil thing I was skeptical to say the least!
If I understand correctly, the light oil weight is only a symptom of the issues concerning new truck engines. In order to meet emissions, engines have become built tighter, turbocharged, etc to get every last ounce per mile. This has led to using lighter oils while dealing with a host of issues.
On a separate note, I think emission scores shouldfactor in reliability scores to move manufacturing back to building stuff that doesn’t put it’s failures on the wallet of the consumer. Reset emission standards and mandate reliability on the same scoring system. I’ll get off my soapbox now…
0W-20 or 5W-20 oil are just fine. Run a quality synthetic and change it more frequently than called for since manufacturers call out oil change intervals that are designed to show lower operating costs and score environmental credits for less waste oil more than maximum longevity.
Modern synthetic oils, even a 0W-20, have nearly identical shear strength as “heavier” 0W-30 or 5W-30 oils. The 0W-20 or 5W-20 will carry away more heat than a heavier weight oil, and theoretically improve power and efficiency by being easier to pump.
In engines with variable displacement lifters, and/or oil actuated cam phasers for variable valve timing I would be cautious of straying too far outside manufacturer viscosity call outs since the oil is also being used as a hydraulic fluid. Which is another great reason to change it more frequently because clean oil that isn’t sheared out of grade is better hydraulic fluid and doesn’t varnish or sludge up tiny little passages in these parts.
So summed up:
Stick with the called for grade, maybe one viscosity grade higher. Buy a quality full synthetic. Buy a quality filter. Change them both every 5000 miles or 6 months whichever comes first.
P.S.
If you and your buddy are truly worried about the longevity of your GM V8’s the oil viscosity used is really a lot less critical than ditching the Active Fuel Management system. This involves a kit with new lifters, tuning, and while you’re there you might as well do a new cam so you can make more poweeeeeeeeeer! Mister Zachary breaks why you should cam it down here. The logic is irrefutable.
I got mine the 1st of October, 2022. It was made during the “chip shortage” and never had the DFM activated from the factory. In fact, it even states so on the sticker and it showed a $50 credit! Shit, I would’ve paid them $50 not to activate it. So mine has been running on all 8 cylinders since I got it, and if a warranty issue ever came up nothing was deleted by some device, it came disabled (or more correctly not enabled) from the factory!
Lifter issues have been endlessly documented. Changing oil weight from manufacture specs is not a remedy. Changing oil at recommended intervals as @ABNAK advised is really the only reasonable thing for the owner to do. If the owner is really “freaked out” perhaps an extended warranty will calm his nerves. Suffering self-induced stress will only serve to cut short the remaining years for a guy in his 70s. However, if he enjoys stress… an engine failure from using straight 40 weight engine oil and an invalidated warranty should help. Good luck.
Yes, it still retains the weak lifter design. That said, at least one potential factor for stressing those lifters has been removed from the equation. Out of curiosity a couple years ago I looked up that new lifter and cam upgrade similar to what you mention. IIRC then it was ~ $6K. Probably $10K+ nowadays!
Man you can’t tell him shit! Crusty old bastard! He “compromised” and used 5W-30. I did some Googling and told him about the tighter tolerances in newer engines, how it could void the warranty, etc. So his idea was to go 30W. SMH.
Next month he’s planning on driving to El Paso from TN and is paranoid he’ll break down along the way. I was like “WTF dude. It’s brand new. It also affects less than 5% of vehicles, so mathematically you’ll be fine.” He bought one of those DFM disablers that also turns off the stupid auto stop/start feature.
I had an '07 (NNBS) 5.3L which I think was the first year having DFM. By now I would have hoped the issues had been worked out. Mine got to where I’d have to add a quart every few hundred miles or so.
Use the oil the manufacturer Specs. They spec it for a reason.
20 sounds thin, but I suspect things in the engine are tight and need it that thin to circulate. A thicker oil is not going to get to where it needs to be, and thats going to cause real issues.
Modern vehicles are shit and people who own them out of warranty are crazy. If you have a warranty, who cares what your lifters do.
I’ve been dealing with LS based motors since 2001 when I got my WS6 and started drag racing.
The guy that built all the engines in that have been my car and did all the tunes has hundreds of LS and LT engine builds under his belt. LS Corvettes running 8s back in 2003 when it was completely unheard of. First NA LS Vette in the 9s (I drove it ) so on and so forth. He recommends 10W30.
I also have a 2021 Silverado 1500 with a 5.3L, I do my own oil changes and I run 10W30 Mobile 1. One of his son’s who moved down to NC and now lives a few minutes from me has a Yukon Denali with the troubled 6.2L. His Yukon is on engine 2 since the first one dropped the lifter. The first engine used the recommended oil, the second; 10W30 Mobile 1. His other son, also now living down here has a Sierra with the same defective 6.2L. From the first oil change he runs 10W30 Mobile 1.
GM recommends lighter weight oil in these vehicles because it helps their EPA gas milage rating.
Tighter tolerances isn’t why they use lighter viscosity oils. It’s to boost mpg numbers. The whole bs about the manufacturer engineers know best and that the vehicle factory manual is fact is absolute garbage.
They might know what is good for the engine, but that might not be what they are telling the public. Manufacturer recommended 10,000 mile oil changes are proof of this. So called “Lifetime” transmission fluids are proof of this. The fact that Toyota has 0W-20 recommended in the US manual, but is 5w-30 everywhere else in the world for the same engine is proof of this.
It’s all about looking good on paper and selling vehicles.
All the manufacturer has to do is get you through the warranty period, and it seems in Chevy’s case, they couldn’t even do that.
This guy lays it out from an oil science standpoint.
0w-20 has been in common use for awhile. My wife’s 2010 Lexus 2GR-FE V6 (VVT-i) uses 0w-20.
The only thing I use a slightly different viscosity oil in is my 2000 Tundra 4.7 V8. The oil fill cap reads “5w-30 Energy Conserving”. But if a person actually reads the owners manual (yeah I know) Toyota recommends 10w-30 if ambient temps are above 0*F. Mild climate here.
Anyway.. no need to fret over manufacture spec 0w-20.
I spent 15 in the automotive industry, working exclusively on german cars. They speced full synthetic before others and we always had those customs who didn’t want to pay for synthetic. The engines really needed it. Other engines, like BMW M engines needed a specific and specialized oil. Again people groaned about paying for it.
In this they never speced light weight oil for fuel efficiency. Maybe now they do? Idk I retired from that industry in 2020.
In non-dry sump engines lower viscosity oil causes less drag on the crank (windage) so an engine can make the same power while working less. This gives a tiny boost in gas milage. It’s nothing crazy, but these guys are trying to squeeze every MPG out of their fleets because the EPA has their balls in a vice. It’s the same idea as the whole auto-stop thing. They don’t care about long term reliability because the warrantee will run out, they just need to hit a MPH threshold.
My first lesson on engine performance related to oil viscosity was in the 1970s. Castrol GTX was being advertised on TV around the clock as the best oil for high performance engines… blah blah blah. So… I tried 20w 50 in my Kawasaki 1000. Damn… it was like riding around with the brake on.
I did some Googling and told him about the tighter tolerances in newer engines, how it could void the warranty, etc. So his idea was to go 30W. SMH.
) so on and so forth. He recommends 10W30.