Toyota now recommends 5W-20 for most cars

[naterprius]

There's a new TSB out on oil. Toyota is now recommending ILSAC GF–4 SAE 5W–20 most new vehicles. They specifically mention NOT to use these oils in older engines due to potential issues with smoking and lubrication.

They also refer the Prius to an older TSB.

All in all, very confusing.

Nate

[Tempus]

<div class='quotetop'>QUOTE(naterprius @ Apr 17 2006, 11:29 PM) [snapback]241311[/snapback]</div>

There's a new TSB out on oil. Toyota is now recommending ILSAC GF–4 SAE 5W–20 for the Prius and others. They specifically mention NOT to use 0W-20 due to potential issues with smoking and lubrication.

Nate
[/b]

TSB Number: EG018-06
Title: Engine Lubrication - ILSAC GF-4 Oil Recommendations

It says - The recommended viscosity grade for this oil differs according to the vehicle model.

Use the recommended grade specified on the oil filler cap or in the Repair Manual or Owners Manual for each vehicle.

For Prius vehicles refer to TSB EG-050-04 - "Engine Oil Specifications"

[jayman]

I don't see how a 0W-20 will cause "smoking" but a 5W-20 won't, since both have the same viscosity at running temp.

I ran Mobil 1 0W-20 over this winter and noticed: improved cold temp fuel economy, *no* oil consumption, and *no* "noise."

As far as engine "wear" I posted my used oil analysis comparing the Mobil 1 0W-30 I ran last summer to the Mobil 1 0W-20 I ran this winter: very low wear results, except the Si as I remove the air filter every month to tap out the loose dusties.

In hindsight, I might as well leave the filter in there for 5-6 months before checking it. Every time I remove the filter from the housing I must be dislodging dust that ends up in the intake.

[efusco]

<div class='quotetop'>QUOTE(Tempus @ Apr 18 2006, 10:09 AM) [snapback]241486[/snapback]</div>

For Prius vehicles refer to TSB EG-050-04 - "Engine Oil Specifications" [/b]

Got a link to that TSB?

[mikepaul]

I'm confused. EG018-06 likes 0W-20, but the Prius-specific version doesn't??...

http://www.alldata.com/tsb/Toyota/11371392...0R-04/5004.html is the only version I can find...

OK, hang on, I'm now less confused. Page 2 of EG018-06 makes a sweeping statement about smoke, but Page 1 defers to EG050-04 for a Prius anyway. That may mean they didn't test in a Prius...

[Tempus]

<div class='quotetop'>QUOTE(efusco @ Apr 18 2006, 11:30 AM) [snapback]241495[/snapback]</div>

Got a link to that TSB?
[/b]

Attached

[galaxee]

on page 2 they do show a list of which engine series can use the 0w20 and 5w20 oils.

while the nz series is listed as being able to take 5-20, they do specifically state that this tsb does not apply to the prius and to refer to the previous tsb specifying prius oil specs.

[efusco]

Now, the way I'm reading this they still recommend 5W30 for Prius..can someone tell me where I'm wrong on that.



And is ILSAC GF–4 the same as synthetic or what? I'm not sure what that designation means.



Found this: http://www.ilma.org/resources/ilsac_finalstd011404.pdf

[jayman]

<div class='quotetop'>QUOTE(efusco @ Apr 18 2006, 11:32 AM) [snapback]241520[/snapback]</div>

Now, the way I'm reading this they still recommend 5W30 for Prius..can someone tell me where I'm wrong on that. And is ILSAC GF–4 the same as synthetic or what? I'm not sure what that designation means.
[/b]

Evan:

There are a *lot* of mixed messages regarding the use of a 5W-20 or 5W-30 in the Prius. When I look up the Maintenance Menu for my 2004 Prius - at the Toyota Canada site - it states both can be used.

When I read of a 5W-20 being "ok" but a 0W-20 will cause "engine wear" and "smoking" the only thing I have to ask is what were they smoking? The issue of viscosity always seems to come up and I find it amusing how some ad writers think a 0W-20 will blow up a motor but a 5W-20 is fine.

The GF-4 oil spec is starting to catch up with older European ACEA oil specs with regards to TEOST (Thermo-oxidation Engine Oil Simulation Test), viscosity increase, cold sludging, hot crown deposits, etc. A conventional oil can be reformulated to meet this spec.

I noticed they still allow an oil to "pass" if it allows stuck oil rings though.

So I'll stick with a good synthetic with a lot of detergents, thanks.

j

[naterprius]

Okay, now I'm confused as well. The note does say for Prius to refer to the older TSB, but it also says for all vehicles to refer to their owner's manual or oil cap. If that's the case, why have the TSB in the first place?

Also, under the main section, why is the exception not listed there (next to "NZ" engines)?

Nate