Why Mercedes 0W40 but Toyota 0W-20?

[SumpChump]

Is it just mileage that Toyota does the 0W-20? I've seen the many discussions of going to 5-20 or 0-30 in 0W-20 applications but never seen why Mercedes can use a 40 weight at 150mph and not starve or friction heat the engine. Whereas I read warnings of 30 weight being too thick in the Toyotas.

I run some 300 mile highway trips in 95 degree summers and just can't believe the 20W is enough. I fact a few times last summer I pulled into Hotel lots after a highway trip and the car clattered (valve clatter?) a bit.

 

[LotI]

Originally Posted By: SumpChump
Is it just mileage that Toyota does spec's the 0W-20? I've seen the many discussions of going to 5w-20 or 0w-30 in 0W-20 applications but never seen why Mercedes can use a 40 weight grade at 150mph and not starvd starve the engine. Whereas I read warnings of 30 weight grade being too think thick in the Toyotas.

I run so some 300 mile highway trios trips in 95 degree summers and just can't believe the 20W is enough.

Fixed it for you.

It's enough. Your engine is water cooled, right?

 

[SumpChump]

Yep water cooled Toyota 2.5L

 

[CT8]

What are the warnings about the 5W-30 would be [too thick]

 

[RedOakRanch]

I've run 150k and counting with my ford explorer using 5w-20 and my summers are 100-115 degrees, no problems. Unless your cooling system can't keep up your oil won't know the temp outside. Racing is a different story but for daily drivers 0/5w-20 is fine.

 

[KenO]

Yes, the Europeans spec a thicker oil due to heat & stress and needing the oil to stay in-grade in severe service, trackdays, etc. Also, long drain intervals. They expect the oil to shear a bit over 10k+ miles. The OCI on the Mercedes is probably twice as long as the Toyota.

 

[d00df00d]

Originally Posted By: SumpChump
Is it just mileage that Toyota does the 0W-20? I've seen the many discussions of going to 5-20 or 0-30 in 0W-20 applications but never seen why Mercedes can use a 40 weight at 150mph and not starve or friction heat the engine. Whereas I read warnings of 30 weight being too thick in the Toyotas.

I run some 300 mile highway trips in 95 degree summers and just can't believe the 20W is enough. I fact a few times last summer I pulled into Hotel lots after a highway trip and the car clattered (valve clatter?) a bit.

The engines are designed differently (some parts of European engines tend to get hotter IIRC) and expected to be driven in different ways (more very high speed for Euro engines, more stop-and-go for American and Japanese engines).

Your 300 mile highway trips in 95 degree summers are just fine. You can be sure that kind of usage was part of the testing regime for your engine. Yes it's hot out, but highway driving is also quite low-stress for the engine and the speed provies steady airflow for cooling.

If you were constantly hurling your car down the Autobahn at maximum speed, then yes, maybe a thicker oil would be warranted. Likewise, most people driving Miss Daisy in German cars might benefit from thinner oils. But in both cases, different oil would be a band-aid for having the wrong powertrain for the job.

Long story short, you can sleep easy.

 

[randomhero439]

^Well said

I agree. Expected usage, mostly. And some engine design. It does interest me that Euro cars do not carry a different oil spec for US models. If it is purely expected usage, nothing would need to be changed other than the text in the manual!

Euro cars have different duty cycles for testing than american or japanese. This is mostly due to the road ways in europe.. speed limits (or lack of), inclines, ect..

 

[Spazdog]

I can (and have) run for hours at 80mph in 110° temps on 5W20 with no adverse effects.

The only thing I can think of is perhaps an extended service interval on European cars.

German cars did have a difficult time with the North American "hot climate". Volkswagen wouldn't release the Golf R here for some time because the United States had a "hot climate" that was detrimental to the turbo 4 (never mind that Subaru, Chrysler, Mitsubishi....even a 30 year old air-cooled Kawasaki run those boost levels). But I don't think Mercedes Benz ever did that. They had inadequate HVAC systems for US market cars for a period of time, but not the engine.

 

[crazyoildude]

5w20 works very well on engines designed for it they are usually tighter engines that require 5w20.
if it says 5w20 use it

 

[Olas]

You guys have a limit on NOX, we don't. Afaik most US cars meet NOX with a rich mix and a late spark to keep the temps down, and this works, but leads to increased dilution from the extra fuel in the cylinder compared to a euro AFR.

Expected usage and roads do come into it but the different emissions laws necessitate different operating procedure..

 

[FowVay]

Olas brings up the key to this whole trend. The Clean Air Act of 1990, driven by the US EPA, dictates that vehicles will start, warm-up and operate with a regulated emissions signature. As technology has advanced so too has the implementation of low-viscosity fluids (motor oil and transmission fluids primarily).

Vehicle manufacturers are required to comply with a structured regulation of total vehicle emissions across their product line. Failure to comply results in very high fines which drives the verbiage in the owners manual. Companies such as General Motors or Toyota have greater sales of one product than companies like Mercedes-Benz sell across their entire product line. The possibility of government fines for failure of compliance is a very strong motivator for manufacturers to get the end-user to use what the vehicle has been tested and approved with. This is why the manuals state to use ONLY a specific viscosity oil in North America yet will often allow different grades in other markets.

The benefits of low-viscosity fluids are purely for emissions/fuel economy reasons. The fact that vehicle testing has shown that the lower grade oils don't lead to premature powertrain failure makes the requirement a win/win for everyone. Look for the introduction of even more applications for low-viscosity fluids. Even the SAE has approved a new low kinematic viscosity grade by introducing the SAE 16 grade oil in April, 2013. By the year 2021 we will definitely see 0W-16 requirements in our manuals.

So why does Mercedes still recommend a high viscosity oil? It's better suited to their worldwide market and the company sells so few vehicles that they just pass the EPA fines along to the consumer. This is typical of all low volume brands in North America.

If your vehicle specifies a low-viscosity fluid then it's best to stick with it for no other reason than it reduces emissions in a large way (up to 18% cold start and 5% operating temps).

 

[Oil Changer]

You can buy a '15 Toyota, drain the FF at 10 total miles and use 0W-40 or 15W-50 year-round and not have an engine/oil related issue for the life of the vehicle. Use what makes you sleep the best.

Originally Posted By: SumpChump
Is it just mileage that Toyota does the 0W-20? I've seen the many discussions of going to 5-20 or 0-30 in 0W-20 applications but never seen why Mercedes can use a 40 weight at 150mph and not starve or friction heat the engine. Whereas I read warnings of 30 weight being too thick in the Toyotas.

I run some 300 mile highway trips in 95 degree summers and just can't believe the 20W is enough. I fact a few times last summer I pulled into Hotel lots after a highway trip and the car clattered (valve clatter?) a bit.

 

[SumpChump]

Wow , you can hey. Neat.

Originally Posted By: Oil Changer
You can buy a '15 Toyota, drain the FF at 10 total miles and use 0W-40 or 15W-50 year-round and not have an engine/oil related issue for the life of the vehicle. Use what makes you sleep the best.

Originally Posted By: SumpChump
Is it just mileage that Toyota does the 0W-20? I've seen the many discussions of going to 5-20 or 0-30 in 0W-20 applications but never seen why Mercedes can use a 40 weight at 150mph and not starve or friction heat the engine. Whereas I read warnings of 30 weight being too thick in the Toyotas.

I run some 300 mile highway trips in 95 degree summers and just can't believe the 20W is enough. I fact a few times last summer I pulled into Hotel lots after a highway trip and the car clattered (valve clatter?) a bit.

 

[tig1]

Originally Posted By: SumpChump
Is it just mileage that Toyota does the 0W-20? I've seen the many discussions of going to 5-20 or 0-30 in 0W-20 applications but never seen why Mercedes can use a 40 weight at 150mph and not starve or friction heat the engine. Whereas I read warnings of 30 weight being too thick in the Toyotas.

I run some 300 mile highway trips in 95 degree summers and just can't believe the 20W is enough. I fact a few times last summer I pulled into Hotel lots after a highway trip and the car clattered (valve clatter?) a bit.


I use 0-20 in both Fords and have ran thousands of miles on trips in hotter temps than 95. Of course not a problem one. I used M1 5-20 in the 70's in engines calling for 10-40, again not a problem one.

 

[benjy]

Mobil I in the 70's was PAO group IV real synthetic oil today all but the EP is group III as are almost all oils labeled "synthetic" in the USA

 

[Clevy]

Originally Posted By: benjy
Mobil I in the 70's was PAO group IV real synthetic oil today all but the EP is group III as are almost all oils labeled "synthetic" in the USA



Wow.


Wanna try again.

You might wanna check your facts before posting incorrect info.
I've now seen 3 posts of yours that are incorrect. Please check your facts before posting. It'll keep you from inserting your foot in your mouth.

 

[Clevy]

Originally Posted By: SumpChump
Is it just mileage that Toyota does the 0W-20? I've seen the many discussions of going to 5-20 or 0-30 in 0W-20 applications but never seen why Mercedes can use a 40 weight at 150mph and not starve or friction heat the engine. Whereas I read warnings of 30 weight being too thick in the Toyotas.

I run some 300 mile highway trips in 95 degree summers and just can't believe the 20W is enough. I fact a few times last summer I pulled into Hotel lots after a highway trip and the car clattered (valve clatter?) a bit.



5w-30 isn't too thick,it's just not optimal. European vehicles have different oil mandates such as longer drain intervals so that among other factors is why they specify a 40 grade.

Use what the manufacturer recommends unless you have circumstances that make going thicker necessary.

 

[Lex94]

All companies pass EPA fines on to their customers...Customers are the only people who give companies money.

 

[edwardh1]

Originally Posted By: Spazdog
I can (and have) run for hours at 80mph in 110° temps on 5W20 with no adverse effects.

The only thing I can think of is perhaps an extended service interval on European cars.

German cars did have a difficult time with the North American "hot climate". Volkswagen wouldn't release the Golf R here for some time because the United States had a "hot climate" that was detrimental to the turbo 4 (never mind that Subaru, Chrysler, Mitsubishi....even a 30 year old air-cooled Kawasaki run those boost levels). But I don't think Mercedes Benz ever did that. They had inadequate HVAC systems for US market cars for a period of time, but not the engine.


yes off topic but I thought some of the 80s and 90s audi vw and bmw hvac systems had inadequate cooling of the passengers also. maybe a hot day in Germany is 85 and in texas its 105. I read a magazine interview with a BMW official in the early 2000s and he said "many of the 90s BMW hvac passenger cooling systems were 30% undersized", which he claimed they had fixed