1999-2009 [Subscribe to Daily Digest] |
Members do not see ads below this line. - Help Keep This Site Online - Signup
Hi,
I found the following link in Bobistheoilguy. It's really good.
It describes the difference between PAO (true synthetic) and semi-synthetic (like Castrol and Saab 5W-30 "blend").
It is important that you guys ask for fully synthetic oil when getting
your car serviced. All Saab dealers carry Saab Long Life fully-synthetic
oil now.
Another tid-bit I picked up from BITOG is that 0W-30 does not
necessarily need _any_ viscosity modifiers. This may explain why all
Mobil 1 (PAO) xW-30 oils do not change viscosity over drain interval.
PAO base-stocks can be mixed to provide spread of 30 without problems.
These base stocks _do_ shear, but they will come back together because
the free radicals have no where else to go but re-attach with base-stock.
On the other hand viscosity modifiers in Group III oils shear and are
less likely to come back together. Instead, the pieces of viscosity
modifiers form sludge, which is harmful to your engine. So, that's why
we think that Jason's (and our) factory fill was "SAE" 5W-30 because PAO
base stock is shear stable and SAE 30 PAO base stock should not shear down
to SAE 20 in 5,000 miles, even with Jason doing the driving :-)
Mobil 1 and Saab fully synthetic xW-30 oils are high quality ACEA A5/B5
oils, and for the warranty period, 2.3 LPT and 3.0 V6 owners can use
Saab fully synthetic 0W-30 oil with confidence (remember you have to ask
for it. Otherwise, you'll get "SAE" 5W-30).
When out of warranty, and dealer service cannot give me any lip about
warranty issues, I'm thinking about switching to Mobil 1 0W-40 for its
superior HT/HS viscosity. The thicker oil does not flow as well during
cold crank, but by then my engine will be nicely plated with molybdenum
so that it is nice and protected during cold crank.
Well, I'm _guessing_ that Saab fully synthetic 0W-30 has molybdenum.
I'll be guessing no longer when I send in a second sample for "virgin"
oil analysis, once I get another oil analysis kit.
VOA of Saab 5W-30 is on its way. I hope the delivery guy didn't drink
it.
If _I_ were lucky enough to be an Aero owner (mind you I'm perfectly
happy with my 2.3 LPT), _I_ would think long and hard about using a
xW-30 weight oil. The higher torque of 2.3 HOT engine requires extra
HT/HS viscosity to protect the high pressure regions such as the bearings.
For this purpose Mobil 1 0W-40 is an _excellent_ choice for you Aero
owner from day 1.
Oh, don't forget about the link. It has good information, unlike the
body of my post :-)
thanks
Jae
posted by 172.171.214...
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
 |
 |
 |
 |
 |
