Do the normal temperature ranges apply for synthetic oil? i.e. If
normal 10w-30 is valid for 20F-90F (just making up numbers) is 10W-30
synthetic limited to the same range?–
James Stauffer
Are you good? Take the test at http://www.livingwaters.com/good/
No, synthetic has lower pour points because it doesn’t have the wax in
it that conventional oil does. It’s best to just go the to data sheet
for the oil you have in interest.
For example
Mobil 1 synthetic 5W30 Esso XD-3 5W30
conventional
pour point -45C -36
flash point 224C
200
viscosity cSt @40C 56 65
viscosity cSt @100C 10 11
Which shows that the conventional oil freezes at a higher temperature
than synthetic, and boils at a lower temperature. At a given cool
temperature the conventional oil is more viscous, i.e. thicker and less
pumpable, but almost the same viscosity hot. This means that there is a
greater viscosity spread, so the synthetic is easier to pump and will
build oil pressure faster when cold, but provides the same protection
against thinning when hot.
here are the full data sheets I used:
http://www.imperialoil.ca/Canada-English/Files/Products_Lubes/IOCAENCVLESEsso_Xd-3_extra.pdf
Only the 0-40 and 0-30 are synthetic on this one
and
http://www.mobil.com/Canada-English/Lubes/PDS/IOCAENPVLMOMobil_1_5W-30.asp#TypicalPropertyTitle
Craig
James Stauffer wrote:>Do the normal temperature ranges apply for synthetic oil? i.e. If
normal 10w-30 is valid for 20F-90F (just making up numbers) is 10W-30
synthetic limited to the same range?James Stauffer
Are you good? Take the test at http://www.livingwaters.com/good/
Craig,
What you say is true, but that’s not the same as the correct viscosity for
the application. Oil needs to be thin enough to get between all wear
surfaces quickly at start up and maintain sufficient viscosity to keep the
parts floating on a layer of oil when the engine warms up. An oil (syn or
refined) that’s too thin for the engine will not develop enough internal
pressure and a thick enough protective layer to keep the parts sufficiently
separated. Oil that’s too thick will require extra pressure to force it
through the oil galleries and out the feed holes. I’ve read that too much
pressure can actually accelerate wear.
Tolerances are so tight in today’s engines, that the recommended maximum
viscosity on many engines in the hottest conditions is 30W. My Chevy S10
pickup calls for 5W-30 for all but the coldest climates. For some
manufacturers, using thicker oil will void the warranty.
In the early days of synthetics, my car experienced a night of bitter cold,
about -30F. It started right up even though it was parked outside. My
transmission, which had refined gear oil was another story. The gear oil,
which was roughly the same weight as the engine oil, was like tar. RPMs
dropped from 800 to 400 just by taking my foot off the clutch. I had to let
the car idle like that for about ten minutes before I could move the shift
lever enough to find the gears.
Synthetics’ wider “natural” viscosity range is taken into account in the
additive package and the stated viscosity. One of the big advantages of
synthetics is that they need less additives so you are getting more
lubricant for the same viscosity range.
Jim,
Synthetic handles extremes far better than refined oil, but you still want
to use the correct viscosity for the temperature range in which the car will
be driven. Because you can go longer between oil changes, you may be able to
drive a full year on the same oil (although not necessarily on the same
filter). That would necessitate a wider viscosity range from the thinnest
winter viscosity to the thickest summer based on manufacturers
recommendations.
Mark-----Original Message-----
From: owner-x300@jag-lovers.org [mailto:owner-x300@jag-lovers.org] On Behalf
Of Craig Talbot
Sent: Thursday, December 15, 2005 2:23 PM
To: x300@jag-lovers.org
Subject: Re: [x300] Synthetic oil temp ranges
No, synthetic has lower pour points because it doesn’t have the wax in
it that conventional oil does. It’s best to just go the to data sheet
for the oil you have in interest.
For example
Mobil 1 synthetic 5W30 Esso XD-3 5W30
conventional
pour point -45C -36
flash point 224C
200
viscosity cSt @40C 56 65
viscosity cSt @100C 10 11
Which shows that the conventional oil freezes at a higher temperature
than synthetic, and boils at a lower temperature. At a given cool
temperature the conventional oil is more viscous, i.e. thicker and less
pumpable, but almost the same viscosity hot. This means that there is a
greater viscosity spread, so the synthetic is easier to pump and will
build oil pressure faster when cold, but provides the same protection
against thinning when hot.
here are the full data sheets I used:
http://www.imperialoil.ca/Canada-English/Files/Products_Lubes/IOCAENCVLESEss
o_Xd-3_extra.pdf
Only the 0-40 and 0-30 are synthetic on this one
and
http://www.mobil.com/Canada-English/Lubes/PDS/IOCAENPVLMOMobil_1_5W-30.asp#T
ypicalPropertyTitle
Craig
James Stauffer wrote:
Do the normal temperature ranges apply for synthetic oil? i.e. If
normal 10w-30 is valid for 20F-90F (just making up numbers) is 10W-30
synthetic limited to the same range?James Stauffer
Are you good? Take the test at http://www.livingwaters.com/good/