Guys, I did it. I switched to 5W30, and took it for a short stop and go traffic plus 15km(9mi) highway run, rough idle is barely noticeable. If I had to give a rating from 0 to 10, previous rough idle was at 10, after switching to 5w30, it’s a 2, maybe 3 at most. If you are not very sensitive, you may not even notice it now. I will keep monitoring and update. It’s definitely worth the switching.

oil used: pennzoil ultra platinum 5w30
filter: purolator boss PBL14477
you will need a 5/8 hose for your filter drain, 2-3 feet is sufficient.

Bonus find 1: drive shaft have grease fitting, all four of them! Gonna order some Amsoil 100% synthetic grease, heck yea!
Bonus find 2: 5w30 oil temp is slightly cooler by 4-5 degrees Celsius than previous 0w20 on the highway which is weird, normally thicker oil run hotter due to higher friction, maybe monitor error or due to exterior temperature.
Bonus find 3: I was hoping the oil pressure will increase, but no, still low. It appears to be Toyota truck’s characteristic.

I live in Canada, rust is always an issue, while I lift my lx600, I give it a nice undercoat with fluid film which I always do with all my cars. Now it’s ready for some Canadian harsh winter!





Please note: I’m not a mechanic, however I do have engineering background and done car repair work as a hobby for over a decade, this is not a recommendation, please do it at your own risk. If you don’t feel comfortable switching the engine oil to 5w30, please stick to the owner’s manual recommendation. If you do want to switch, buy quality engine oil meets GF6 and keep your purchase receipts for oil and filter in case of warranty dispute.

 

Hold on…. There is a filter housing drain? I have just been cracking the filter loose and letting it drain down onto my face and then kinda into the drain pan.

If I keep it stock am going with the 0-30 Esp euro mobile 1 next. That literally has the best numbers and can be bought at Walmart.

Unfortunately I am waiting day by day for lexus to release a tune to correct some things and I may have to use a tuner I already bought and with the power add i will be going 0W-40.

These make so much power per liter, really impressive. No clue why they suggest thin low viscosity oil. At least their thin transfercase fluid has a strong additive package to make up for it.

 

5/8 hose is optional, but it will make it less messy. I suspect the W40 oil would completely remediate the rough idle issue. But w40 viscosity oil is not on the official repair manual. 5W30 would do it for now. When my warranty expires, I will definitely try the W40 oil. I am not a big fan of thin oil neither. Too many future potential issues for little fuel savings. Not worth it.

I’ve heard many good things about euro formula engine oil, never used it myself yet. I have bought lots of pennzoil ultra platinum and Valvoline restore and protect, need to use them first lol. Please keep us updated if you try the w40 oil.

thanks for your reply. Cheers

 

What are your thoughts on 0W-20 as this is what the dealer is using?

 

I’m not sure I can answer your question perfectly, as it’s quite broad—but I’ll give it a try.

• 0W20 is a great engine oil—a remarkable product of modern petroleum engineering, as are 0W30 and 0W40. Back in the conventional oil era, these formulations were almost unimaginable. I remember discussing this topic with my lab group about 15 years ago.
• Is Toyota 0W20 good? Yes, absolutely. It’s made by ExxonMobil. While I haven’t personally done an oil analysis on Toyota-branded oil, I suspect it uses a Group III base stock with an additive package somewhere between regular Mobil and Mobil 1.
• Can you safely use 0W30 or 5W30 in an engine designed for 0W20? In most cases, yes. The entire operating viscosity range of 0W30 falls within that of 0W20 at operating temperatures, so an engine designed for 0W20 won’t experience anything radically different with 0W30. On the other hand, you shouldn’t substitute 0W20 in an engine that calls for 0W30—it won’t meet the film strength or protection needed at high temps. As for 5W30, it’s designed for climates where the ambient temperature stays above -20°C (-4°F), while 0Wxx oils are formulated for colder conditions down to -25°C (-13°F). As @JoeRedneck mentioned, 0W30 is a suitable alternative to 0W20, though it’s harder to find in North America and often more expensive to manufacture.
• The more important question is why automakers recommend 0W20, rather than whether it’s “good” oil. Engines operate across a range of viscosities depending on temperature (even 0W20 starts thick when cold and thins out when warm). It’s not realistic to say one oil fits all—from Texas heat to Canadian winters. If you’re tracking your car, a racing expert might suggest 10W50, even in an engine that calls for 0W20 during daily driving in cold weather.

So, why does Toyota recommend 0W20 across the board? I can see two main reasons:

1. Simplicity – One oil spec simplifies service across global markets and reduces risk of error by technicians and corporate liabilities.
2. Fuel efficiency incentives(same reason to drop V8 for turbo V6) – Lower viscosity oils can yield slightly better fuel economy, which helps manufacturers meet government efficiency and emissions standards(more incentives to the manufactures).

But as a consumer, I’m more concerned with engine longevity than squeezing out a few extra MPGs. That’s why the right conventional oil is still better than the wrong synthetic viscosity, no matter how premium it is.

As a personal example—we’re about to leave on a road trip from the Canadian Prairies to Texas in my wife’s 2020 Lexus RX350. For this long summer highway drive, I changed the oil to 5W30. There’s really no compelling reason to use 0W20 in these conditions other than to save maybe $10 in fuel over the whole trip. The 2GR-FKS engine purrs like a kitten on 5W30!

 

GF-6A oil is designed for fuel economy and emissions.

0w-20 is supposed to help with fuel economy and emissions. (But all it did was make my LX unbearably rough)

Toyota has a global commitment to reduce carbon emissions. So therefore every dang dealer better stock 0w-20.


As mentioned the 0w-20 motor oil runs across the range of viscosity a 40 weight oil has as it warms up.

The colder the climate the thinner you need to start off at. But they still recommend 5w-50 in the Shelby Mustangs and Corvettes for track duty regardless of climate.

Was watching a video where an engineer from Next Gen Valvetrain was talking about since the advent of low viscosity transmission fluids that cars in the north have much lower transmission failures. Because the viscosity is higher. He talked about how he ran LV fluid instead of ULV in a Navigator he bought just to show the ultra low viscosity fluids arent needed. (Although I wouldn’t recommend that).

I do though have a case of Redline D6 that is going into my LX600 as soon as i get a chance. It is at the upper end of the viscosity variance for Toyota WS.

And Toyota WS. They label it a “lifetime” fluid in some models because of environmental standards on imported vehicles. According to posts I have read on Tacomaworld.

 

This is a possibility and not a certainty, but that may be due to the homogeneity of the GTL (gas-to-lube) oil base, or it may be polar vs. non-polar normal oil. If I put a polar oil, like an ester-based oil (Redline, some other boutique oils, Lubegard, etc) it will drop fluid temps a few degrees. The polar oil will bond to the metal better in a film and increase heat transfer. I’ve both read about this in technical materials, as well as observed it with careful monitoring in my own vehicles.

I know roughly how the PP is made, but I don’t know the final structure of the molecule.

 

I used Redline differential and transfer case gear oil for my wife’s RX350 and my previous trucks. Great products! The only downside for me is extreme cold flow(-35C due to where I live) is comparable to Toyota WS(not very good), I just bought a case of AMSOIL transmission fluid to try out, it claims to have better cold flow.

 

thanks for your input, that makes sense. Anything to help the engine run cooler is good.😁

 

I’m not sure what arguments they make, BUT the advent of LV trans fluids nearly perfectly coincided with the advent of six speed automatics and a real upward evolution in quality for some of the worst offending (highest failure rate) transmission makers - GM, Ford, and ZF. This may be more a product of coincidence than causality. They may have a point that eludes me, but IME I can think of other reasons.

LV fluids had two real changes a) lower viscosity for minuscule mpg gains, but also) b) much more complex friction modifier package to deal with pulse-width (pwm) torque converter control and the heat it generated. Newer ulv fluids haven’t been widely deployed enough AFAIK to make a real statement on LV vs ULV.

In extreme cold, transmissions have a “floor” temperature that external cooling can’t really overcome. IME** taht is in the 110-120F range and that’s perfectly adequate for healthy operation; the oil temp will get to that even -20F exterior operating temps in a reasonable time. Cold weather isn’t the true challenge on transmissions regardless of fluid type, it’s heat and fluid neglect.

** I have rigged an auxiliary temperature sender in the mid-body of a GM transmission and monitored internal temps at a wide variety of temps and usage conditions to get familiar with these dynamics.

 

WS is lv ot ULV?

Its a point of contention for bitogers that claim its an archaic/non synthetic fluid that is worse then many multi vehicle atfs. personally im a proponent of using oe WS fluid when new, and then switch over as the vehicle piles on miles.

 

That might make sense. From my past examination, I realized the companies had two very different lubrication philosophies:

- Redline tried to build (it appeared to me - don’t take this as gospel everywhere) the purest oil they could, with the fewest additives necessary, out of expensive and capable ester oil stock. They could deliver oil that was very pure, required very few additives, kept seals in perfect shape, kept the inside of the engine spotless, and improved heat transfer this way. I was told by someone who should know/could judge, for example, their 10w-30 motor oil was in fact just straight 30 of their base stock. It was SO good, it could pass the SAE test for 10 winter with no additional additives, pour depressants, or thinner base stock blending. That is truly remarkable. This is like the star soloist on stage who leaves you in awe for hours at a show.

- Amsoil takes a totally different approach, and tries to build the most complex, intricate, capable oil by maximizing the individual properties of a huge range of base oils and additives. This is trickier to pull off than it sounds - a lot of those bases and additives work AGAINST each other inherently, or eat seals. It takes skill. This is like a world-class symphony in unbelievable coordination and harmony.

Both are totally legit philosophies. I tend to like redline’s more - BUT I could see how Amsoil could meet that -30C point better in your application. There really is no one “true” best lubricant across the board - there are some dogs out there (like WS, for example), but nothing is absolute. Really interesting when you tear into the science and complexity of it. Oil blender must go mad sometimes trying to work through all the trade-offs and conflicts.