Oil return ports

I am not trying to start a oil debate thread .
I worked for Titus will Ford and Toyota when the Tacoma first came out .
I remember several vehicles needing their engines replaced under warranty due to oil starvation because the oil return passages were to small and would get clogged , I don't remember which engines had the problem.
I now own a 2017 Tacoma Limited with the tow package .
I am towing a boat at close to my max weight limit .
I wanted to upgrade the oil since I am running the engine pretty hard while towing .
Has anyone been inside one of these V-6's and noticed the size of the oil return passages .
I have been considering using 20-50 synthetic but don't want to have the heavier oil cause problems due to having troubles returning to the oil pan .
I know this seems like a pretty stupid question but if I had not seen several engines replaced
due to the oil passage size I wouldn't be asking .
Thanks .

 

I'd be more concerned about keeping the fluid(s) cool, than the oil type.
I have not been inside the 3.5. But oil starvation is not a reported issue.

I recommend changing the fluids more frequently. Transfer case, and Differentials too.

In all honesty, going off my experience. You'll likely have issues with the boat before the truck.

 

It does have a engine oil cooler but now that you brought it up I should probably try to figure out how to monitor the trans temp .

 

Then you know that these V6 engines only use 0/20 or 5/20.

 

I like 20w50 would be a very bad idea. The VVT is oil controlled, not sure how it would respond with 50 weight. You might be creating more problems than your trying to solve.

 

Do not put 20-50 in any modern engine, the bearing clearances are so small now that your more likely to have a lubrication related failure from too thick of oil than your are from too thin of oil. Also alot of engine components such as the VVT system rely on the correct oil being used to work properly, incorrect weight oil will cause issues.

Use the manufacturer recommended oil weight and grade, if you want to "upgrade" your oil then use a high quality synthetic oil of the correct weight and grade for your engine.

 

It is not a dumb question. (The only dumb question is the one that doesn't get asked)

Anyway, I cannot emphasize this point enough as others have already stated. DO NOT RUN 20W50 OIL UNDER ANY CIRCUMSTANCES.

Thicker (higher viscosity) oil is NOT designed for these engines and will flow LESS through the oil passages that exist.

Use 0W20 fully synthetic and change it every 5000k miles. That is the only oil upgrade you need. Do a drain and fill of your tranny fluid. Depending on how often you tow your boat and the distance traveled, this could become an annual maintenance item. Consider a cooling system flush depending on your mileage and visible radiator condition. Carry a spare serpentine belt. Air up your tires and make sure your trailer bearings are good. And that's pretty much all I would suggest doing.

Machine work or extrude honing your engine's blocks oil ports (passages) is going to be cost prohibitive and I doubt you will even find anyone to do it. You would be better off selling your truck and buying one with heavier towing capacity.

Find a scan device that you can monitor your trans temp if desired. Others will have recommendations in this regard.

 

Really wish people would stop bible thumping 0W-20 and spreading inaccurate information.

The 2GR-FKS engine is engineered to use oil weights 0W-20 to 15W-40. Which oil you choose is partially dependent on the temperature and climate of where you are driving and partially dependent on how you are driving.

"An oil with a higher viscosity may be better suited if the vehicle is operated at high speeds, or under extreme load conditions." - Direct quote from the manual.

The only reason Toyota declines to actually name other oil weights that you can use is because of U.S. federal laws; laws that next to no citizen wanted but were implemented by an increasingly rogue and subversive Congress.

Look at manuals for the 2GR-FKS in countries outside the U.S., they all say the same thing: use 0W-20 to 15W-40.

I use 5w30 Mobil 1 in the Fall/Winter and 10w30 Mobil 1 extended performance in the summertime. The regular 5w30 states flashpoint of 467 degrees. The 10w30 extended protection states a flashpoint of 483 degrees. Our trucks make these motors run very hot at the pistons. Torque is high up in the rev band at 4000+RPM. At redline the top of a piston can reach well over 500 degrees and some of this heat will transfer to the cylinder walls and shear your oil. If you tow, drive at high speeds, or drive up hills at high RPM 0W-20 is not the ideal oil. That being said plenty of people use it without engine failure.

As for the debate on the size of the oil ports and clearances on this engine. Take a look at the Car Care Nut's channel on youtube. He's torn down 2GR-FKS engines and you can clearly see the oil ports are the roughly the same if not exactly the same size as any other older but still modern Toyota engine. Also would recommend for anyone still questioning this issue to watch some videos on how temperature affects oil viscosity.

Surely what brand of oil to use or what additive pack to get in it is a never-ending debate. Why the viscosity debate persists is mystifying to me. Use the viscosity that suits your driving style and temperature/climate.

But no, don't use 20-50. That is actually too thick for this motor.

 

OP, this doesn’t address your exact question.
But you may find it of interest. As it goes into a lot of detail on the engine.

 

Would like to see this law that says we have to specify a certain weight of oil, manufacturers are going to lighter oils for fuel economy reasons yes but I'm not aware of any law that says what that oil weight has to be (quite a few vehicles still use 5W-30 and 5W-20). They are also designing engines around using lighter oils by having tighter tolerances and also how the systems controlled by oil pressure are expected to operate.

Granted the 2GR only has VVT but I've been to multiple classes on VVT, VVL, and cylinder deactivation and every one stresses to us that you have to use the correct oil for these systems to operate properly and also provide examples of what happens when you don't (ranging from trouble codes to engine damage). Some vehicles even have a specific DTC for incorrect oil type that will set if oil pressure deviates too far from an expected value.

Maybe your right and the 2GR can handle whatever oil you wana put in it but I can't recommend anything other than what the manufacturer specifies should be put in which for us is 0W-20.

 

The law is called physics

 

The EPA literally dictates to the manufacturers what can be printed in the owners manual, what the maximum and minimum mileage intervals of maintenance can be, etc. I know researching substantive law and policy is difficult -it is made this way on purpose, but all the data you need to see that you are spreading misinformation is available at your finger tips through some diligent searches.

https://www.chevronlubricants.com/e...viscosity-oils-hit-the-automotive-market.html

https://www.enginelabs.com/engine-t...s-the-latest-spec-in-the-world-of-engine-oil/

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CAFE Law and Associated Regulations: https://www.nhtsa.gov/laws-regulations/corporate-average-fuel-economy#light-duty-vehicles
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My 2GR runs exactly what it is designed to, which is a 20, 30, or 40 weight oil based on driving style and temperature and climate.

See again page 574 of the U.S. 2017 Tacoma Owner's Manual: "The 20 in 0W-20 indicates the viscosity characteristic of the oil when the oil is at high temperature. An oil with a higher viscosity (one with a higher value) may be better suited if the vehicle is operated at high speeds, or under extreme load conditions."

Now to answer the OP's question accurately: You can use 0W-20 to 15W-40 in the 2GR-FKS engine based on your area's climate and your driving style. Do not use a 50 weight oil. See the Mexican Owners Manual for the 2GR-FKS below.

 

Thanks!
That is a wonderful source of detailed information for my library.

Q: does a similar document exist for the transmission?

 

You didn't show a single law that says the EPA tells the manufacturer what oil weights they can recommend in the manual. Ford must be breaking the law by telling GT500 owners to use 5W50.

 

It's based on averages across the vehicle brand and different models. They use a formula to determine what the ranges are, what can be printed in the manual in order for EPA certification to be granted, etc.

It's all on the EPA's website buried amongst thousands and thousands of pages of technical jargon and legalese. And it isn't a just a simple law that states this, its federal administrative code written by lifetime federal government employees that you didn't vote for and you can't fire. Congress passes legislation which is a basic foundation of a law. The framework or meat and potatoes of the law is written by the executive branch's agencies that are in charge of implementation of the law, in this case the EPA.

https://www.govinfo.gov/content/pkg/FR-2024-04-18/pdf/2024-06214.pdf
See page 313

If you want information deeper than this you are going to have to do your own research. My knowledge is a mile-wide but inch-deep. Our government and the law is a behemoth. I suggest everyone invest some of their time in figuring out how things really work. For every good reason behind a law or a policy there is a real reason. Diving into the inner workings of government law is a difficult and time consuming task, but for a citizenry to be informed it must be done.

 

I think there is some misunderstanding here. The EPA mandates CAFE which is the average fuel economy across the brand lineup. If they don't meet the CAFE, they are fined for it. They use thinner oils to help meet CAFE. What they design and test the engine on and get fuel economy estimates for, is what they have to recommend to the owner to use in the USA. Hence why the USA owner's manual says only 0W-20, or 5W-20 temporarily.

In other countries there are no such rules, so the Tacoma in Mexico gets the go-ahead to use all of the viscosities listed earlier in the thread: 0W-20, 5W-20, 5W-30, 10W-30, 15W-40. Obviously, alternates of the same weight are fine too, so 0W-40, 5W-40, and 10W-40 would also work.

20W-50 is not that far from 15W-40. It would likely be just fine. It is not technically listed by Toyota, so probably best to stay with 15W-40 and below.

There are a lot of misconceptions about VVT and that it won't work if you use the "wrong" oil. That isn't really true. VVT needs oil, it doesn't need a specific oil. Any motor oil will get the VVT job done. It just needs oil pressure. If VVT needed a very specific viscosity oil, then we would be screwed when the temps drop. Viscosity changes way more due to temp and a cold 0W-20 is much thicker than a hot 15W-40 or 20W-50. If it truly wouldn't work without the listed viscosity, we'd be experiencing constant issues at various temperatures due to the oil thickening or thinning too much due to normal temperature swings.

 

I feel like 20w-50 would be overkill for this engine. Especially since you're just towing a boat. Not a rectangular uhaul across the country. A 40wt oil will be more than enough for you.

With the oil cooler you'd be fine with a high quality 20wt too but I get it.. I run atleast 0w/5w-30 year round and have for 120'000Kms.

 

As far a document like the engine? No, not that I am aware of.

But a member here put together a thread on the transmission with a lot of good information.

https://www.tacomaworld.com/threads...omatic-in-the-2016-write-up-with-pics.361114/

 

So its exactly what DM93 said but you called it misinformation. The EPA doesn't tell them what oil they can use but heaver oils need to be tested and may impact CAFE.

 

Nobody said it won't work but the performance of it is affected by oil viscosity, when it is commanded to move it's expected to move in milliseconds. If it doesn't move quickly enough the PCM sees it as a fault, I'm not saying this is the case with this engine but it is with others.

This is why some engines have went away from hydraulic actuation of certain things and instead use an electronic actuator because it can react far more quickly than a hydraulic one.

Some of the other stuff such as on some cylinder deactivation systems the locking pin on those lifters have to move at an exact point in the engine rotation, if they don't they get damaged.

I've yet to see any evidence that using the oil weight and grade specified by the manufacturer for the region the vehicle is sold in has resulted in premature failure, I have seen evidence that deviating from that has caused failures so as a technician I can only recommend using the oil specified in your owners manual. Of course it's your truck so you can use whatever you want in it but I can only recommend what it says in the manual.

You have to also note that oil and fuel quality and availability as well as emissions standards and thus engine calibrations can vary alot from country to country

I won't disagree with you about the bureaucracy involved but that's what we are currently stuck with and it looks unlikely to change anytime soon.