George Macdonald wrote:
> On Sun, 22 Feb 2004 02:11:22 GMT, "Steve" <abc@123.com> wrote:
>
>
>>My 2003 HX coupe (CVT trans.) calls for 5W-20 motor oil. It says so in the
>>owners' manual and there's a sticker right on the engine block that says
>>"5W-20".
>>
>>I'm due for an oil change but none of the places around me have 5W-20 --
>>they all tell me just to use 5W-30 (which is all anybody around here seems
>>to stock).
>
>
> Most of the lube mfrs now make 5W/20 in some of their grades so it is
> available - your local vendors are probably just reluctant to dedicate
> shelf space to oil which is recommended by only two auto mfrs, Ford and
> Honda. The one notable exception is Mobil1 which is not available in
> 5W/20; to tell the truth I think it may be quite difficult to make a true
> synthetic with such a narrow viscosity range.

There are a few synthetic blends in 5W-20 weight. One is Castrol
Syntec, which some believe is dubiously labelled as such. The other
is Pennzoil "SUV, Truck, and Minivan", although it may be hard to find.

Mobil 1 0W-20 is labelled as suitable for 5W-20 applications. I
theing that's the factory oil weight for Honda hybrid engines. The
original weight of Mobil 1 25 years ago was 5W-20.

>>Q: Why does the HX coupe w/CVT call for 5W-20 (instead of a more "common"
>>weight) ?
>
>
> The question has been much discussed here in the past if you want to search
> for previous posts at http://groups.google.com/advanced_group_search
>
> It's everything from a plot to make our engines fail earlier to the
> advancement of metallurgy and lubricants technology.:-) My POV is that
> it's something the EPA is ramming down our throats by way of the auto mfrs
> as an "energy conserving" measure. The difference in mpg is barely
> measurable and easily voided by different individual driving habits.

I saw the spec sheet for Havoline motor oil. All weights from 5W-30
to 20W-50 and single weights contained 0.103% zinc (by weight). The
exception was 5W-20, which is 0.112%. A zinc compound is an anti-wear
additive - right?

<http://library.cbest.chevron.com/lubes/compprd9.nsf/c88c682625e06af6882568db00737ce8/d1099203c4293c4f88256b5600791e6c/$FILE/PCMO-2210.pdf>

BTW - I've suspected that Chevron Supreme motor oil may be the same
since the ChevronTexaco merger. However - the spec sheet seems to be
different.

<http://library.cbest.chevron.com/lubes/compprd9.nsf/c88c682625e06af6882568db00737ce8/c748bacbd316e79a88256a0000786813/$FILE/PCMO-20.pdf>

>>Q: If I use 5W-30 (instead of 5W-20), what are the consequences?
>
>
> My opinion: the 5W/30 willl give you a slight extra margin of engine
> protection, over the 5W/20, at high ambient temps, say >90F. I'd use the
> 5W/30. In fact, if you don't live in the frost belt, I'd use 10W/30.
>
> The next time you go to the Honda/Acura dealer parts dept, they may have a
> counter mat which lists the oil grade reqts by model. Take a good look at
> at it and ask yourself why Honda still recommends 10W/30 for the S2000 and
> NSX.

These are extremely high revving engines. However - the Integra GS-R
and other DOHC VTEC engines are similar and 5W-30 is the recommended
weight. MY new WRX recommends 5W-30, but says 10W-30 and 10W-40(??)
are acceptable for normal driving above. The manual even advises
using 30, 40, 20W-40, or 20W-50 if you're towing or it's really hot.
Europeans are used to using heavier grades (with longer drains), and
their motor oils are subject to a higher standard than API SL. OTOH -
they typically won't keep a car beyond maybe 60K miles.