Engine Oil in extreme hot climate

Hello guys,

First technical post here and of course it's an engine oil question.

Just got myself a 2018 Tacoma TRD Off-Road with 38K miles without much history so I'm going over a few maintenance chores myself.

I'm stuck at one main topic and that's which oil grade/viscosity to go with.
I have the 2GR-FKS engine, the manual says 0w20 but it does not mention anything about hot climates as this car is only sold in the US.

I live in Dubai, UAE. At night, the temps are around 90F and in the morning it can go up to 122-124F in the summer.

Our driving conditions are mostly highways, and when it comes to off-roading, it's all desert so it's mostly high revving.

Should I really stick with 0w20? Or will I be ok with the Toyota/Lexus 5w40 fully synthetic?

 

I would think with those temps, you'd want 10w40 full synthetic. 5w40 is probably fine but I would want more if the temp never gets down below 90F.

 

I'd suggest to shift to a 5w40 or 5w50.

I don't think the 0w20 is a good choice in those temperatures.

There are oil viscosity vs temperature charts that can guide you on which viscosity to use for your environment.

 

5w30 full synthetic.

 

You can go as thick as 20W-50 in the 2GR-FKS:

 

I would suggest sticking with the recommended oil. Temp isn't mentioned for a reason. While the climate can reach 120, the operating temperature of your engine is still well above that. The engine is designed to work with 0W-20. I'd be more concerned about proper cooling than oil viscosity.

 

Sounds like vegas to me . Ive stuck with 0w20 for me and its been good since 2016.

 

Thanks for the info guys and thanks @verlaryder for the screenshot, that helps a lot!
I'm gonna go with 5w40 on this oil change, see how it behaves and switch to 0w20 on the next oil change, then switch to 5w30 and see which fits best.
Will probably run 6K miles on the 5w40, 3K miles on the 0w20 and then 6K miles on the 5w30.

I found out that locally on some Toyota cars, they use 0w20 on some cars with 3K miles changing intervals.

 

Some parts of the US like Arizona, Nevada and California (Death Valley) get up to those temps as well. If you have 0W30 available it would cover the whole temperature range, otherwise use 5W30. I'd avoid a xxW40 oil because it may be too thick at operating temp and cause the oil filter bypass valve to open more often, letting unfiltered oil through.

 

Camry engine in a truck ?
or
A truck engine in a Camry ?
which is it? LOL

Regardless, when I want critical info on the operation or maintenance of my vehicles, I always ask random dudes on the interweb. Never ask your local dealer what the factory recommends or believe what the owners manual says ;-)

 

This may be a dumb question but..... if the vehicle's coolant system is functioning properly, why would one worry at all about ambient temps in the 120s?

 

I found a similar page from the Australian owner's manual for our old '17 Corolla (2ZR-FE). It spec'd 0W-20 in the US and similar weights as the Camry's V6 in Australia. I tried 5W-30 Pennzoil Platinum in it and the engine was slightly — but noticeably — quieter/smoother, but did lose some fuel economy. Normally it was easy to get MPG in the upper 30s on the highway but with the thicker oil I had to work (hang back/be super calm) to get it up to 34-35. At the next oil change I switched it back to 0W-20 (Mobil 1 EP) and it regained the couple of MPG it lost on the 5W-30.

I only know enough about oil chemistry to be dangerous, but from casual perusing over at BITOG it seems like the Mobil 1 EP 0W-20 has the best quality base stock of all the Mobil 1s so I have stuck with that over the years. The 0W-20 EP and the 0W-16 AFE (used in the new DI 2.0 and 2.5 engines in the Corolla/Camry) are mostly Group IV/PAO (like 60-70%) vs. only like 20% in most of the other offerings.

 

fwiw my truck idles for hours some days in this heat. Last week the high was around 118 (122 on the dash) Sent oil samples out after 10k miles and 12k was recommended after that. I run M1 0w20

 

I'd talk to a mechanic there personally.

I know in some shops in Arizona they don't use 0w20 at all, they stick with 5w30.

I agree that 0w20 seems too thin and I would run a 30 or a 40.

PSA guys, the first number is the winter rating, it has no bearing on this guys issue.

 

Makes no difference. The engine manages its temperature regardless.

 

I'm of the opinion that there is a slight chance that the Phds that formulate motor oils/additive packages through research and testing might have a higher understanding than your typical nose picker on forums. There have been a few Blackstone tests posted through the years, I'm not scared of 0w20 anymore.

 

At some point I gotta quit over thinking everything, escape the analysis paralysis and trust the mf smarter than me.

 

Just a general FYI:

The "w" in 5w 30 represents the viscosity at 0 deg F. Kinda moot if living in a 100 degree desert year-round ;-)

The other viscosity rating represents how long (time) it takes for a specific amount of oil to flow through a specific-sized orifice.

Lower viscosity takes less time, higher viscosity takes more time. 40 weight takes longer than 20 weight.

Doubling the viscosity from 20 to 40 just makes the oil that much harder to squeeze between bearing and journals or piston skirt and cylinder bore. Not a problem on an air-cooled Harley Davidson engine that was designed last century with tolerances a mile wide, but I'm guessing not that great in a modern engine with clearances in the ten thousandths of an inch. You need the oil on those bearings Right Now. Not 'soon' ;-)

Since most of the wear on an engine is at startup, when fuel is washing what little oil there is away from piston skirts and cylinder walls, the above is kinda important.

To summarize: Doubling the recommended oil viscosity in a modern water-cooled engine is great for less fuel economy, more frequent maintenance and of course, more engine wear ;-)

EDIT: A previous post referencing the fact that in a modern water-cooled engine with temperature controls ambient air temps are relatively moot is spot on.

 

5w30 call it a day. Very common formulation, synthetic or dino juice doesn't matter if you are going to change out before the 10K OCI.

 

Ok, with that being said, why does Toyota reccomend viscosities higher than xw20?

What if you were to run a 0w30 or 0w40?