[Mgs] oil question

[Richard Ewald]

Paul,
FTR I was a technical person for Volvo Cars of North America for 15 years
until I retired earlier this year.  While the zinc issue is a valid concern
for a 40+ year old car, it is not a valid concern for current production
engines.  In case you were not paying attentions engines are just a tad
different now then they were when my B was new.  The composition of the
engine is way different (aluminum vs cast iron), the metallurgy of those
metals is way different, as well as the temperatures that the oil has to
cope with.
for what's it worth I attended a technical presentation on oils back in
June.  the showed the results of a 200 hour test between a SD (available in
the mid 1960s when my B was new) rated oil and a SL (current) rated oil.  At
the end of the 200 hours they tore down the engine filled with SL oil, and
there was no detectable wear.  Which is as it should be.  The SD engine
suffered a bearing failure at about 168 hours, rendering it unable to finish
the test.

Bottom line is the guy that designed and built the engine knows way more
about it than you do.  In the case of MG all of those guys are dead or in
the old folks home.  In the case of Volvo they are still building the same
engines, and having worked for the company I have spoken with them on this
subject.  The factory recommendations is what they run in their own cars.
As I said before they know more about that engine than you do.

when this post first came out, I responded directly to David without copying
the list.  Here is that reply.

>>David,
I can answer this one.  Up until March of this year, For the last 15 years I
was a technical training instructor for Volvo Cars of North America.
Your wife's S60 came from the factory with a full synthetic 10W-30 oil rated
ACEA A1/A5 (API SM grade)
In the United States to keep the warranty in effect you need to use a 10W-30
weight oil rated with the API certification SM (maybe SL for the early
S60's, I don't recall just which year the SM oils came out)
In my experience any decent dino oil now a days will be SM.  To get the ACEA
A1/A5 spec you have to go to synthetic route.  While this is not a bad idea,
it is not required.
DO NOT RUN ANY OIL HEAVIER 10W-30.  This engine has lots of little tiny oil
passages and too heavy an oil will not circulate fast enough.  Damage can
result.
If you live in cold country check your owner's manual for cold temp oil
recommendations.
FWIW Volvo recommends Castrol.

One last comment, the factory oil filter is superior to any aftermarket
filter I have ever seen.  Owing to how tightly the factory filter is folded,
it has almost 2X the filter media as many popular aftermarket units.  Well
worth the extra couple of bucks IMHO.

If you have any further questions, feel free to drop me an e mail.
Rick


>>Given the recent discussion of the removal of zinc from oils, I am not
sure that the handbook recommendations are valid anymore (at least for
a car that is out of warranty).