On Wednesday, February 1, 2006, at 04:22 PM, Marshall Booth wrote:
Mercedes revised the recommendation (236.2) for PS fluid in about
1987/1988 (236.3). They use an oil that's a little less viscous than
type A ATF (which is less viscous than Dexron II/III) and that isn't
treated with the Lubrisol additives. It is far superior (doesn't
stiffen
up) to conventional Dexron in very cold weather (although the
synthetics
that meet the Dexron/Mercon spec seem just fine). The Mercedes fluid is
recommended for ALL Mercedes PS systems, but ATF is still permissible
for any system that was originally factory filled with ATF (most any
car
built before 1987). Using ATF in cars up to about 1995 will not cause
any major problem, but in cold weather, the steering may be more than a
little stiff.
Here's the result of some research on the subject by Dr Eric
Chowanietz:
I've felt things stiffen up with conventional Dexron III/Mercron and
earlier Dexrons but never had the stiffness with Mobil 1 or Amsoil
synthetic tranny fluid. I haven't moved and it still gets to 25 below
around here.
It seems Eric has mixed feelings on the application but he is spot on
about the conventional ATF/Dexron in the cold going on to say it could
have better corrosion and lubricating qualities.
Johnny B.
I Mac Therefore I am
