ACEA A1 vs ACEA A3

[Paranoil]

Hi,

Could someone please tell me what the basic difference is between an oil rated ACEA A1 and one rated ACEA A3?

i.e. if you had two oils, both 5w30 semi-synthetic API SL, but one was ACEA A1 and the other A3, what would be the difference? The only thing I can determine from the ACEA website is that the A1 rating has a lower HT/HS value. What effect, good or bad, does this have on the oil, and what would happen if you put ACEA A1 oil in an engine designed to run on A3 rated oil?

Thanks

 

[haley10]

In 5w30, I would assume the A3 oil would be a "synthetic", but the A1 might not be. What about the other B or E ratings that go along with it??

Over here the only oils I've seen that may be suitable for extending drain intervals begin with A5 or A3.

 

[Losiho]

Is A1/B1 basically the same as A5/B5 ?

 

[bulwnkl]

quote:

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Originally posted by Losiho:
Is A1/B1 basically the same as A5/B5 ?

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The diference according to the ACEA website is that the A5/B5 is a long-drain oil whereas the A1/B1 is not. They are otherwise the same.

 

[Dr. T]

The differenceis that an A3 oil must meet HT/HS of 3.5 or greater whereas the A1 does not. This is the only difference.

Unless your engine specs out A1 as the proper oil, the A3 will be a better 5-30 as it has a greater number of addatives required and/or the viscosity is on the thicker end of the 30 spectrum in order to qualify it as an A3 oil.

 

[Jimbo]

If you use A1 in place of A3 (when required) you are risking excessive engine wear. On the other hand, A1 oils are the European equivalent of "Energy Conserving" in North America.

 

[TooSlick]

The ACEA, A1/B1 oils are roughly equivalent to the API, SL/CF formulations. An API,SM formulation would not have the detergency needed to meet even the "B1", light duty diesel specification.

The A5/B5 formulations are the low vis equivalent of A3/B4 and used in some newer European motors that tolerate thinner oils.

TS