FW: pentosin substitutes revisited - verrrrrry interesting stuff

[Livolsi, Stephane]

>     As far as your ZF info goes, they are saying that if you have central
> hydraulics (e.g. brake assist/self levelling) then you need to be using
> G002/Pentosin/whatever they call it round your way.
>
Actually, I was trying to point out that ZF does NOT specify G002/Pentosin
which I found very curious.  I suspect that Audi chose Pentosin as a
supplier and therefore specifies only G002 as acceptable, even though there
may be other hydraulic oils out there that are safe to use in Audi systems.
I actually think the wording would be something along the line of ' use only
a fluid that meets or exceeds the specifications of Pentosin G002000"  So
it's the specs that are important, not the brand.  However, what I found was
that it appears that G002000 actually is unique and there are no other oils
that meet or exceed it's specifications.  Read on.

I had a bit of time on my hands so I did a bit of comparison between a few
hydraulic oils, combination hydraulic/tranny fluid, and pentosin CHF 7.1 and
CHF 11S.  The 'other' oils include Chevron, Mobil, Amsoil and other less
well known brands even getting into the Ford/New Holland and other tractor
brands.  My search led me to the tractors because, as I found out, many of
them use a common reservoir to supply hydraulic fluid to the wet clutch, wet
brakes (however that works), transmission and the hydraulic system.  The
comments on friction were particularily interesting which generally
indicates that the tractor fluids should not be used in our systems.
What I found was that many of them are very close to the pentosin specs
EXCEPT in 2 categories - Viscosity Index and 'Viscosity at -40C'.  The
viscosity index for 7.1 and 11S is 340 and 320 respectively.  ALL of the
other oils that I found that spec'd similar to pentosin had much lower
numbers including Mobil DTE 13M.  The DTE comes in at 140.  Let me be
honest, I DON'T KNOW WHAT THIS MEANS.  For all I know a lower number may be
better.  Does anyone know?

Also, the viscosity for DTE (as an example) at -40 C is 5110 whereas for
pentosin it is listed at <1100.  Again, I don't know if this is good or bad.

The flash point for 'other' oils tends to be 20-40 degrees C above pentosin.
This I suspect is good.


Let's face it, if you have a good hydraulic system, the cost of pentosin
shouldn't be an issue because you use so little of it (provided your system
doesn't have the 'seive' option).  My reason for looking into this is
availability (try asking for pentosin around here if you want people to look
at you like you have 2 heads) and also potentially cheaper hydraulic system
flushes.

Just some food for thought

Stephane