SM, GF-4 or A5. Which is best?

[Audi Junkie]

I see in another post that an A5 oil lasts longer and a CH4/CI-4 runs cleaner. What about the comparison of SM and A5? Why do we see blends like Syntec Blend 10w-40 meeting A3 but the hot new GF-4 oils are supposedly not as long-lasting or clean-running. I saw a US mfg specs that called for a double-length test, but ACEA A-Series tests are like 10x longer than API. Worth a mention is the fact that Delo, a dino HDEO meets A3, CH-4/CI-4+. Were does SM and GF-4 rank and why would it be lower? We already have $2 A3 blends and $1.75 HDEOS that possibly out perform the newest SM/GF-4 oils. Am I missing something?

 

[Blue99]

The SM/GF-4 ratings do not directly correlate with ASCEA. New SM/GF-4 rated 5W-20's & 5W-30's are only ASCEA A1 oils.

ASCEA A3 are heavier viscosity oils with greater than 3.5 HTHS. So A1 is not better than A3, than GF-4, or CI-4. All are simply different spec's.

Some of the synthetics with extended drain ratings will no doubt be both SM & A5.

BTW, Audi, Chevron lists Delo 15W-40 as ASCEA E2,E3 & E5, but not A3. The HTHS probably meets A3, but Chevron does not list it as an approved rating.

 

[Audi Junkie]

The BOTTLE, man. Check the BOTTLE!

 

[Sin City]

ILSAC GF-4 is a significant upgrade over ILSAC GF-3. ACEA A5 is a high performance low viscosity oil suitable for extended drains and as such should still be superior to the new ILSAC GF-4 specification. I have compared the specifications for each and since some of the tests are different it is hard to give a direct comparison. For extended drains I would prefer to use an ACEA A5 oil over an oil that is only rated GF-4.

 

[Gene K]

quote:

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Originally posted by Blue99:
BTW, Audi, Chevron lists Delo 15W-40 as ASCEA E2,E3 & E5, but not A3. The HTHS probably meets A3, but Chevron does not list it as an approved rating.

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That's funny... It says A3 on the Jug...

Gene

 

[Blue99]

Gene, when a question regarding Delo 15W-40 approvals is asked, hopefully the Chevron Tech Rep's do not respond, "Just a minute, let me pull a bottle off the shelf & check the label".

While Delo 15w-40 no doubt meets A3 specs, Chevron does not list ASCEA A3 on the current Delo 15W-40 product data sheet.

Due to the phosphorous levels, it would make sense that the use of Delo in gas engines/catalytic converters will be discouraged by Chevron.

From the data sheet:

code:

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Chevron Delo 400 Multigrade meets:

• API Service Categories CI-4 PLUS1, CI-4, CH-4,

CG-4, CF-4, CF, CE2, CD2, SL, SJ, SH2, SG2

• ACEA European Service Categories E5, E3, E2

• JASO Asian Service Categories DH-1

• Global Service Categories DHD-1

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[friendly_jacek]

quote:

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Originally posted by Norm Olt:
Why would Delo have a gasoline API classification of SL/SJ, etc. if it were going to be harmful to cat's?

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Finaly this silly topic turned into interesting point.
I reserchered this point extensively due to the fact that I use rotella 5W40 in my car with cat.

The P level in SL is somewhat murky. If you study the issue, SL does not limit P, but GF-2 and GF-3 do (up to 1000 ppm). ILSAC's GF standards cover only oils up to XW30 in weight. Oils XW40 and up are not covered by GF and thus P is technically not limited in those. However, most SL oils, even many 5W40/15W40 HDEO, have up to 1000 ppm P but with more robust Zn (up to 1500ppm).

In short, SL XW40 or thicker oil can have more than 1000 ppm P, most likely not, do VOA if in doubt.
Similar situation will exist with SM I suspect.

This situation with P limits is crazy. I read a study showing no correlation between P % in oil vs amount of P deposited in cat. However, some compounds containing P are more volatile than others. ILSAC people are too dumb to understand that.

 

[Norm Olt]

Why would Delo have a gasoline API classification of SL/SJ, etc. if it were going to be harmful to cat's?