Does anyone know why the Castrol TWS 10w-60 specified for e46 m3, and other modern m engines, is formulated under the old API SJ classification rather than SL or SM? I've done a UOA on the oil currently produced (and labeled as API SJ) and it has a rather modest zddp content (around 600-700 ppm) so it could probably qualify (if that's the right word) as a SM. Just curious.
Castrol TWS - Why API SJ ?
- Thread starter m6pwr
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Well I’ll speculate –
I think the basic issue is that the Castrol simply doesn’t care about the API rating for this product. The target market for this oil is mainly BMW M engines such as the S54 and some collateral use by other racing/track users of other makes and models. Accordingly, what matters most is the BMW approval followed distantly by the ACEA rating, which is really just a concern inasmuch as it is a precursor to the BMW approval testing.
In regards to the API testing, consider that the SJ rating was “current” from 1996 to until 2001, which covers the period of time in which I believe the TWS first came to market, or at least to the popular market and the BMW spec for the M engines. So the initial API approval testing was likely done to the SJ standard.
It is also important to note is that the SL standard has some significantly different engine test requirements than the SJ.
• The Sequence IID test gets replaced by the Ball Rust Test, which substitutes a special test machine for the actual engine test.
• The Sequence IIIE test is replace by the Sequence IIIF test, which uses a different GM test engine than the earlier test
• The Sequence IVA test is newly added and requires a 100 hour duration test on a specific Nissan test engine
• The Sequence VG test is newly added and requires a 216 hour duration test on a specific Ford engine
(Plus there are some other differences in the standards which affect the criteria and test methodology, although they are generally similar).
So couple the significant retest requirements with the fact that the target market really only values the BMW approval regardless of the API rating, and it just doesn’t make business sense to expend the effort to get an SL or SM rating.
I think the basic issue is that the Castrol simply doesn’t care about the API rating for this product. The target market for this oil is mainly BMW M engines such as the S54 and some collateral use by other racing/track users of other makes and models. Accordingly, what matters most is the BMW approval followed distantly by the ACEA rating, which is really just a concern inasmuch as it is a precursor to the BMW approval testing.
In regards to the API testing, consider that the SJ rating was “current” from 1996 to until 2001, which covers the period of time in which I believe the TWS first came to market, or at least to the popular market and the BMW spec for the M engines. So the initial API approval testing was likely done to the SJ standard.
It is also important to note is that the SL standard has some significantly different engine test requirements than the SJ.
• The Sequence IID test gets replaced by the Ball Rust Test, which substitutes a special test machine for the actual engine test.
• The Sequence IIIE test is replace by the Sequence IIIF test, which uses a different GM test engine than the earlier test
• The Sequence IVA test is newly added and requires a 100 hour duration test on a specific Nissan test engine
• The Sequence VG test is newly added and requires a 216 hour duration test on a specific Ford engine
(Plus there are some other differences in the standards which affect the criteria and test methodology, although they are generally similar).
So couple the significant retest requirements with the fact that the target market really only values the BMW approval regardless of the API rating, and it just doesn’t make business sense to expend the effort to get an SL or SM rating.
Hi,
m6pwr - I have often commented on this product on BITOG. A search may help you understand more about its background
Castrol's Edge Sport 10W-60 sold here is API SM/CF compliant along with ACEA A3/B3/B4. It is targeted at racing/sport applications
m6pwr - I have often commented on this product on BITOG. A search may help you understand more about its background
Castrol's Edge Sport 10W-60 sold here is API SM/CF compliant along with ACEA A3/B3/B4. It is targeted at racing/sport applications
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Thanks to all above for their input. Makes sense. Actually I'm a big fan of TWS and have used it exclusively in two different e46 m3's - - and I have followed all the posts from Doug Hillary about TWS for as long as I've been on BITOG. I just wanted to learn all I could about the oil.
FWIW, API seems unaware of the SM version of TWS. The only Castrol 10W-60 they list is the FORMULA RS as a CF/SJ.
http://eolcs.api.org/FindBrandByViscosity.asp?Viscosity=10W-60
http://eolcs.api.org/FindBrandByViscosity.asp?Viscosity=10W-60
Also, curiously enough, the Castrol Australia website lists two very different 10W-60 oils -
* Edge Sport which is API SM but not BMW approved
* TWS which is BMW approved but API SJ
http://www.castrol.com/castrol/castrolhomepage.do?categoryId=3000
EDIT -
Along the same lines, Castrol UK also lists two 10W-60 oils
* Edge which is BMW approved and API SJ
* Edge Sport which is API SM but not BMW approved
* Edge Sport which is API SM but not BMW approved
* TWS which is BMW approved but API SJ
http://www.castrol.com/castrol/castrolhomepage.do?categoryId=3000
EDIT -
Along the same lines, Castrol UK also lists two 10W-60 oils
* Edge which is BMW approved and API SJ
* Edge Sport which is API SM but not BMW approved
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Castrol Germany lists three 10W-60 oils
* EDGE FORMULA RS 10W-60 at API SM but not BMW approved
* TWS at API SJ and BMW approved
* Formula RS which for some reason brings up a server login prompt when you try and access the technical data sheet
* EDGE FORMULA RS 10W-60 at API SM but not BMW approved
* TWS at API SJ and BMW approved
* Formula RS which for some reason brings up a server login prompt when you try and access the technical data sheet
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