Going off the Gold standard

[Mike Arman]

In local Discount Auto Parts today, saw a gallon jug of hydraulic fluid for
$4.99, and a five gallon pail for $20.00.

Got to thinking about Green Gold at $11 per liter or thereabouts, and
wondered exactly *what* makes this stuff so expensive - this isn't rocket
science.

Went to the Pentosin.de website, went to the english version, and looked up
central hydraulic system fluids. The java link is wrong, and it gives you
something about a brake fluid bleeding trolley or cart, so I poked around
the site a little more.

At the top, there is a selection bar - clicking on "motor lubricants" gives
you "central_hydraulic_fluids.html" which is what I was looking for -
(check the brower bar on mouse-over - java-speak).

Anyway, here are the specs for Pentosin 7 and 11:

Pentosin 7 has a specific gravity of .84, a flash point of 130 degrees C, a
pour point of greater than -60 degrees C, and a viscosity index of 340. It
meets ISO 7308 and DIN 51 524.

Pentosin 11 has a specific gravity of .83, a flash point of 154 degrees C,
pour point of -55 degrees C, and a viscosity index of 320. Note that it
meets the SAME ISO and DIN specs!

Both are mineral oil basis. (Doesn't say anything about synthetics!)

The difference is that 11 has slightly better tempearature specs than 7,
which is why you can put the new stuff (11) into an older car, but you
shouldn't put the old stuff (7) into a newer car. With specs like these, it
may actually NOT make any difference since not too many of us listers
operate our cars at -50 degrees C or +130 degrees C either.

11 is also recommended for "agricultural" applications (tractor
hydraulics?) and "special" uses. 11 has a higher temperature range than 7,
and is very slightly thinner.

Now that's what I *KNOW*. I also *have heard* that both flavors of Pentosin
have anti-wear and anti-foaming additives, but I don't know how much of
each and what kind they have.

Now that I have identified the specifications of "green gold", I went to
the Valvoline website and got annoyed - it is very clumsy, and won't send
e-mails. Persistence pays, and I found a 1-800 number, and called for tech
support. The guy at Valvoline referred me to someone in the lab, and I have
left a message on his voice mail.

It strikes me that now that we know the specifications of this stuff, we
ought to be able to find a USA sourced replacement for a heckuva lot less
money. It just might be time to go off the "gold standard" . . . 



Best Regards,

Mike Arman