About the only difference is the Vis at 40C. I would go with the thinner 5W30. Well, there is a 10C difference in flash point.
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10w30 or 5w30 1998 Jaguar XJ8
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Originally Posted By: tina
Hi, is there a big difference between the 10 degree flash points between 5w30 and 10w30? Thanks!
There is very little relevance between an oil's flashpoint and any performance specification, unless you are worried about it bursting into flames in the presence of an ignition source.
Hi, is there a big difference between the 10 degree flash points between 5w30 and 10w30? Thanks!
There is very little relevance between an oil's flashpoint and any performance specification, unless you are worried about it bursting into flames in the presence of an ignition source.
4WD
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Nothing - you made a good choice
Originally Posted By: fordf250123
That makes no sense. You want the most free-flowing oil at startup. The most wear occurs on startup, so you want the least viscous oil available. 5w-30 should be put in the car.
Not the way it works. Flow does not equal lubrication. Presence of oil does. All engines except those with external primers start and run on residual oil film until other systems take over. Pistons, rings, cylinder walls, timing chains, accessory drive gears like distributor and oil pump all rely on sling oil or splash oil. They don't get pumped oil, ever.
Pumped oil is for valve gear mostly. It's at the top of the engine and to well shielded to get any sling oil off the crank.
As long as you are above the cold flow limits of the oil, all oil pumps will fill the galleries and passages at the same rate for 5W, 10W, 30W, etc. They are positive displacement pumps.
Thicker oil might cause the oil filter to by-pass the media if it's a small filter ... But, that is usually not a major concern.
102,000 miles so it has some bearing wear. My guess is the owners manual says something like 5W-30 as recommended. My wife's Jag runs on QS Defy 10W-30 and has been happily doing that for 177,000 miles
Is your V8 Jag supercharged?
Most likely I'd run Valvoline Maxlife 10W-30 as long as the oil pressure gauge looks OK and the low oil pressure light does not flicker. If either are ever flickering, switch up to 10W-40
That makes no sense. You want the most free-flowing oil at startup. The most wear occurs on startup, so you want the least viscous oil available. 5w-30 should be put in the car.
Not the way it works. Flow does not equal lubrication. Presence of oil does. All engines except those with external primers start and run on residual oil film until other systems take over. Pistons, rings, cylinder walls, timing chains, accessory drive gears like distributor and oil pump all rely on sling oil or splash oil. They don't get pumped oil, ever.
Pumped oil is for valve gear mostly. It's at the top of the engine and to well shielded to get any sling oil off the crank.
As long as you are above the cold flow limits of the oil, all oil pumps will fill the galleries and passages at the same rate for 5W, 10W, 30W, etc. They are positive displacement pumps.
Thicker oil might cause the oil filter to by-pass the media if it's a small filter ... But, that is usually not a major concern.
102,000 miles so it has some bearing wear. My guess is the owners manual says something like 5W-30 as recommended. My wife's Jag runs on QS Defy 10W-30 and has been happily doing that for 177,000 miles
Is your V8 Jag supercharged?
Most likely I'd run Valvoline Maxlife 10W-30 as long as the oil pressure gauge looks OK and the low oil pressure light does not flicker. If either are ever flickering, switch up to 10W-40
Originally Posted By: kschachn
Originally Posted By: tina
Hi, is there a big difference between the 10 degree flash points between 5w30 and 10w30? Thanks!
There is very little relevance between an oil's flashpoint and any performance specification, unless you are worried about it bursting into flames in the presence of an ignition source.
The way I see it, and I admit to be reading the tea leaves here a bit, is that a higher flash point and a higher density and a lower pour point can all imply a slightly better base stock (especially if PP drops a lot) or thicker and less volatile base stock, is used.
For the above two oils, the pour point is the same, but the 10W30 has slightly higher density and slightly higher flash point, so that would be my pick. Given the price is the same and the cold starting performance is acceptable.
But just splitting hairs here.
Originally Posted By: tina
Hi, is there a big difference between the 10 degree flash points between 5w30 and 10w30? Thanks!
There is very little relevance between an oil's flashpoint and any performance specification, unless you are worried about it bursting into flames in the presence of an ignition source.
The way I see it, and I admit to be reading the tea leaves here a bit, is that a higher flash point and a higher density and a lower pour point can all imply a slightly better base stock (especially if PP drops a lot) or thicker and less volatile base stock, is used.
For the above two oils, the pour point is the same, but the 10W30 has slightly higher density and slightly higher flash point, so that would be my pick. Given the price is the same and the cold starting performance is acceptable.
But just splitting hairs here.
Originally Posted By: boostedtsiawd
I went with mobil super 5000 10w30 what do you think?
10w30=
API. SN
Gravity, API 31.3
Specific Gravity 0.8693
Pour Point, °C (°F). -36(-33)
Flash Point, °C (°F), 230(446)
Viscosity
cSt at 40°C 68.8
cSt at 100°C 10.5
CCS, cP 6,300 @ -25ºC
MRV, cP 17,000 @ -30ºC
Viscosity Index 140
It looks good to me mate.
When using conventional mineral oil, I always prefer a 10W30 over a 5W30, as the 10W30 contains less polymer VII's and should be less volatile.
If I need a 5W30 then I prefer a (full or semi) synthetic.
The OM chart above says 5W30, 10W30 and 15W40 are all acceptable oil grades. Plus the modern API SN is much better than the old SH. So it looks like you are good to go.
I went with mobil super 5000 10w30 what do you think?
10w30=
API. SN
Gravity, API 31.3
Specific Gravity 0.8693
Pour Point, °C (°F). -36(-33)
Flash Point, °C (°F), 230(446)
Viscosity
cSt at 40°C 68.8
cSt at 100°C 10.5
CCS, cP 6,300 @ -25ºC
MRV, cP 17,000 @ -30ºC
Viscosity Index 140
It looks good to me mate.
When using conventional mineral oil, I always prefer a 10W30 over a 5W30, as the 10W30 contains less polymer VII's and should be less volatile.
If I need a 5W30 then I prefer a (full or semi) synthetic.
The OM chart above says 5W30, 10W30 and 15W40 are all acceptable oil grades. Plus the modern API SN is much better than the old SH. So it looks like you are good to go.
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Originally Posted By: boostedtsiawd
so does the 10w30 and 5w30 flow the same at cold start?
What temperature? Anything above freezing yes. Anything moderately below, still yes.
so does the 10w30 and 5w30 flow the same at cold start?
What temperature? Anything above freezing yes. Anything moderately below, still yes.
according to this which one will flow better during cold start? or there both the same?
5w30=
API Service Classification SN
Gravity, API 32.9
Specific Gravity 0.8607
Pour Point, °C (°F) -36(-33)
Flash Point, °C (°F), ASTM D 92 221(430)
Viscosity
cSt at 40°C 63.95
cSt at 100°C 10.7
CCS, cP 6,080 @ -30ºC
MRV, cP 26,800 @ -35ºC
Viscosity Index 158
10w30=
API Service Classification SN
Gravity, API 31.3
Specific Gravity 0.8693
Pour Point, °C (°F) -36(-33)
Flash Point, °C (°F), ASTM D 92 230(446)
Viscosity
cSt at 40°C 68.8
cSt at 100°C 10.5
CCS, cP 6,300 @ -25ºC
MRV, cP 17,000 @ -30ºC
Viscosity Index 140
5w30=
API Service Classification SN
Gravity, API 32.9
Specific Gravity 0.8607
Pour Point, °C (°F) -36(-33)
Flash Point, °C (°F), ASTM D 92 221(430)
Viscosity
cSt at 40°C 63.95
cSt at 100°C 10.7
CCS, cP 6,080 @ -30ºC
MRV, cP 26,800 @ -35ºC
Viscosity Index 158
10w30=
API Service Classification SN
Gravity, API 31.3
Specific Gravity 0.8693
Pour Point, °C (°F) -36(-33)
Flash Point, °C (°F), ASTM D 92 230(446)
Viscosity
cSt at 40°C 68.8
cSt at 100°C 10.5
CCS, cP 6,300 @ -25ºC
MRV, cP 17,000 @ -30ºC
Viscosity Index 140
Originally Posted By: kschachn
Originally Posted By: boostedtsiawd
so does the 10w30 and 5w30 flow the same at cold start?
What temperature? Anything above freezing yes. Anything moderately below, still yes.
+1 to what kschachn said.
It's more about pumpability than flow. No problems at all above freezing.
A 10W oil is good down to 0F or -20C (or even a touch lower), but 0F starts is when I would change from a 10W to a 5W, above that you are fine.
Originally Posted By: boostedtsiawd
so does the 10w30 and 5w30 flow the same at cold start?
What temperature? Anything above freezing yes. Anything moderately below, still yes.
+1 to what kschachn said.
It's more about pumpability than flow. No problems at all above freezing.
A 10W oil is good down to 0F or -20C (or even a touch lower), but 0F starts is when I would change from a 10W to a 5W, above that you are fine.
Originally Posted By: SR5
It's more about pumpability than flow. No problems at all above freezing.
A 10W oil is good down to 0F or -20C (or even a touch lower), but 0F starts is when I would change from a 10W to a 5W, above that you are fine.
Yeah I originally made a distinction between flow and pumpability but then deleted it considering the question.
It's more about pumpability than flow. No problems at all above freezing.
A 10W oil is good down to 0F or -20C (or even a touch lower), but 0F starts is when I would change from a 10W to a 5W, above that you are fine.
Yeah I originally made a distinction between flow and pumpability but then deleted it considering the question.
Again, at what temperature?
Originally Posted By: boostedtsiawd
according to this which one will flow better during cold start? or there both the same?
5w30=
API Service Classification SN
Gravity, API 32.9
Specific Gravity 0.8607
Pour Point, °C (°F) -36(-33)
Flash Point, °C (°F), ASTM D 92 221(430)
Viscosity
cSt at 40°C 63.95
cSt at 100°C 10.7
CCS, cP 6,080 @ -30ºC
MRV, cP 26,800 @ -35ºC
Viscosity Index 158
10w30=
API Service Classification SN
Gravity, API 31.3
Specific Gravity 0.8693
Pour Point, °C (°F) -36(-33)
Flash Point, °C (°F), ASTM D 92 230(446)
Viscosity
cSt at 40°C 68.8
cSt at 100°C 10.5
CCS, cP 6,300 @ -25ºC
MRV, cP 17,000 @ -30ºC
Viscosity Index 140
Originally Posted By: boostedtsiawd
according to this which one will flow better during cold start? or there both the same?
5w30=
API Service Classification SN
Gravity, API 32.9
Specific Gravity 0.8607
Pour Point, °C (°F) -36(-33)
Flash Point, °C (°F), ASTM D 92 221(430)
Viscosity
cSt at 40°C 63.95
cSt at 100°C 10.7
CCS, cP 6,080 @ -30ºC
MRV, cP 26,800 @ -35ºC
Viscosity Index 158
10w30=
API Service Classification SN
Gravity, API 31.3
Specific Gravity 0.8693
Pour Point, °C (°F) -36(-33)
Flash Point, °C (°F), ASTM D 92 230(446)
Viscosity
cSt at 40°C 68.8
cSt at 100°C 10.5
CCS, cP 6,300 @ -25ºC
MRV, cP 17,000 @ -30ºC
Viscosity Index 140
Above 0F I would use 10W30
Below 0F I would use 5W30
Below 0F I would use 5W30
Originally Posted By: kschachn
Originally Posted By: SR5
It's more about pumpability than flow. No problems at all above freezing.
A 10W oil is good down to 0F or -20C (or even a touch lower), but 0F starts is when I would change from a 10W to a 5W, above that you are fine.
Yeah I originally made a distinction between flow and pumpability but then deleted it considering the question.
No Worries.
I knew you knew that, as I often enjoy reading your posts. Just adding a touch of detail for new people who may be reading.
All good mate.
Originally Posted By: SR5
It's more about pumpability than flow. No problems at all above freezing.
A 10W oil is good down to 0F or -20C (or even a touch lower), but 0F starts is when I would change from a 10W to a 5W, above that you are fine.
Yeah I originally made a distinction between flow and pumpability but then deleted it considering the question.
No Worries.
I knew you knew that, as I often enjoy reading your posts. Just adding a touch of detail for new people who may be reading.
All good mate.
Another issue i noticed ever since i put chevron techron fuel system cleaner in the near empty tank and filled up with shell premium 93 gas the car dont start as fast as it use to in the cold. Is it possible the previous owner was using regular gas and now the car is confused?
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