GM is reccommending that 6.2 V8 owners switch from 0W-20 to 0W-40 synthetic motor oil as result of recent bearing failures.
What do you think about doing this with our LS500 engines?

 

If you haven't seen this video explains the science of the oil weight change issue ( )

I don't have a LS500 yet but it seems that theoretically changing to a 0w-40 would increase the oil film thickness helping out in the low rpm high load drive conditions. Id imagine that specific load is more applicable to the trucks and large suv's than the LS500 sedan. Just a guess but I assume Toyota / Lexus wouldn't officially make the change due to fuel economy targets?

i have my old sc430 and an Subaru with the turbo FA20. They both recommend 5w-30. I do plan on switching to a 5w-40 after watching this video and digging more into what the "40" side of the oil weight means in terms of film thickness. To each their own.

 

Corporate Average Fuel Economy rules have forced manufacturers to do all kinds of dumb things like start-stop, 5,000lb vehicles with little 4 cylinder engines, transmissions with 2 or 3 overdriven gears, cylinder deactivation, thinner motor oils.
I ran 40 wt motor oil in a small block V8 GM boat motor for 20 years with never a problem, can’t imagine it being an issue in a car in the South where we live. I give my cars a little more warm-up time when they are cold, but that’s about it.
Apparently oil additives shouldn’t be used, so don’t go pouring some thick mystery stuff in with your motor oil.

 

Not sure why you wouldn't follow the engineer's recommendations for arguably one the most reliable car brands on the globe. Today's engines have far closer bearing tolerances and are precision manufactured relative to those of decades ago.

 

I'm new to this forum and own a 2022 Lexus LS500. I'm not an oil expert or an engineer, but with the twin turbochargers, I'm hesitant to use a heavier oil than recommended. I've been using the factory-recommended 0W-20 motor oil without any issues, and I make sure to change it every 5,000 miles. With a vehicle this expensive, I don't see the point in taking any unnecessary risks.

 

You're totally fine following Lexus/Toyota in putting 0W-20 into your cars. There's nothing wrong with that.

I think the OP's comment is that this is the first time we're seeing an engine RECALL where the OEM correction is to change oil from a 0W-20 to a 0W-40. Which all it does is increase the oil film thickness at operating temp (100 C or 212 F). So it provides more cushion in the GM 6.2L V8 against bearing damage. Heres the SAE J300 2015 charts the Oil Geek references in his video.

Tighter main bearing clearance or not (GM vs. Lexus) the higher weight (20 vs. 40) at operating temp (100 C) does provide more cushioning between metal surfaces. And more drag too, so less fuel economy. We're talking micro inches difference of film thickness here... There's always trade offs.


SAE Oil Grades (2015) chart

SAE Oil Grades (2015) Comparison chart

 

The manufacturer is specing 0W-20, not because it is better, but because fines for not meeting the CAFE mileage standards are enormous.


The government CAFE fines for auto manufacturers are based on how far a manufacturer's fleet of vehicles falls below the required fuel economy standards. The fines are not per vehicle, but per each tenth of a mile per gallon (0.1 MPG) that the manufacturer's fleet average is below the required standard.

Specifically, the fines are:

• $14 per 0.1 MPG: for model years 2019-2021.
• $15 per 0.1 MPG: for model year 2022.

These penalties are multiplied by the number of vehicles in the manufacturer's fleet that are sold domestically.

 

Sounds like you've convinced yourself. Do it today, and let us know how it goes in 50k miles. The majority of us aren't about to outsmart the Japanese engineers.

 

That thicker oil requires more time and force to pump, dissipates less heat, and won't circulate where a thinner oil was designed to. But I say go for it, take the risk. Report back after 50k or so miles and let us know how your experiment worked.

 

I would only use what Toyota engineers have tested and recommended as per the global manual. Select regions like Japan and US have stricter regulatory environments, and thus have different requirements, but even then you can only go so thin (have yet to see the new toyota 0w8 oils in v35s). Toyota has always made it simple, select the ambient temps limits, select the correct oil numbers within those limits, and run a duty level rated oci.

0w40 is not on the list. Im referencing this, and it seems 0w/5w for the cold rating and a 30 covers the spectrum and limits. Again any of the oils in the manual are fine, as long as there are appropriate for the temps and duty cycle.


https://lexusmanuals.com.au/document...-dec-17-sep-18



Side note:
No engine is "designed for" a particular oil grade. An engine can be designed to tolerate thinner grades of oil without excessive wear but that's it. Oil doesn't "get places" faster either. Either it is being pumped by the oil pump or it is not. The winter rating illustrates whether the oil can be pumped or it won't.

"0W flow" is only important over a 5W when the temperature is below -35 or so. Is this your operating environment? And it's not really about flow either. It is about cranking and pumpability. No 5W-30 would have the same "cold flow" as a 0W-20. One is a 30-grade while the other is a 20-grade. Even if it were about "flow" then if the one with a 5W winter rating was better it would be required to be labeled as a 0W. That's how SAE grading works. Pour point does not adequately represent the cold-weather performance of a motor oil. It has deficiencies.

Motor oil recommendations in owner's manuals are rife with undisclosed outside requirements that are anything but technical.

 

I’m getting my oil and filter changes at my dealer which is 100 miles away.

This is an inconvenience and a costly one, but my car is under a Lexus Certified warranty. I want all service records to be on record.

The dealer service department told me they use bulk Mobil1 synthetic. I was a little surprised as I expected a Toyota/Lexus branded motor oil. They also attemp to sell me some sort of snake oil additive which I decline.

On my other Lexus which is an ‘02 I request a certain oil which my local independent shop purchases. I watch as they change the oil and filter.

I’m putting blind faith in the Lexus dealer’s service. Wish there was a way the customer could watch the service.

So, I’m getting whatever motor oil the dealer uses, but I have elected to get oil and filter changes at around 6,000 mile intervals instead of the recommended 10,000 miles.

 

When I ask for a sample, my dealer will fill up my Blackstone sample vial and I send it to them for analysis. It tells me everything I want to know about my engine internals.

I truly doubt that your Lexus dealer uses anything but Lexus oil, despite what they told you. What does your invoice say? Using non-OEM parts is a slippery slope.

 

[QUOTE=Bigoofy

I truly doubt that your Lexus dealer uses anything but Lexus oil, despite what they told you. What does your invoice say? Using non-OEM parts is a slippery slope.[/QUOTE]

My invoice says 9 #00279-0W201-01GTMO 0W20 BK Sp WTY @. $5.90 = $53.10

I don’t know if that is a Lexus part no., but two different service advisors have told me on at least two occasions that they use Mobil1.

 

Getting maintenance done at an indy is fine, as you would have receipts/work order, but I also understand the reasoning of why you would want dealer oil changes for documentation purposes and more so building rapport with your servicing dealer.

Tgmo Oil is nothing special, but you can request that they specifically use TGMO for an oil change provided you cover the upcharge. The manual just specifics API SN (SP is current) i believe which can be had from any blender or supplier; so mobil 1 is fine. You can use better oils from M1 such ESP or boutique oils with stringent approvals and such, but Toyota has not issued such guidance. With the 5k/6 month I would not overthink it.

 

That's a Toyota pn. Not sure why they wouldn't be using Toyota oil when that's what they stated they used. Not sure who makes Toyota oil. Perhaps it's ExxonMobil.

I know that Subaru, for instance, uses Idemitsu.

A quick google search says that ExxonMobil does make Toyota oil. It's the additive package that matters. If the Toyota package is different than Mobil1, I suppose that could be a problem.