Does oil viscosity have anything to do with RMS leak?
#17
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Here's my take:
-My car is MY 02. At that time 0W-40 didn't exist. The owner's manual recommend 10W-40. So I try my best to put in 10W-40.
-I know that Joel Reiser of PCA Tech Guru preaches on the 0W-40 for it's thin characteristics to immediately power the hyd lifters.
**My take is to keep using what the car was intialy/engineered for and as the the owner's manual specifies. Which on my model year and older 996 is 10W-40. Track 15W-50. I believe that too thin of an oil has more capillary characteristics or has a high potential that it will seep through vs thicker oil.
Like the lister above mentioned "Porsche DOES NOT recommend 0W40 oil, but only includes it on the approved list"
for model year 02 and older owner's manual, pg 170 states that:
Use only engine oils labelled as API SH or SJ, or ILSAC GF 1 and viscosity grades of SAE 10W-40 or higher.
-My car is MY 02. At that time 0W-40 didn't exist. The owner's manual recommend 10W-40. So I try my best to put in 10W-40.
-I know that Joel Reiser of PCA Tech Guru preaches on the 0W-40 for it's thin characteristics to immediately power the hyd lifters.
**My take is to keep using what the car was intialy/engineered for and as the the owner's manual specifies. Which on my model year and older 996 is 10W-40. Track 15W-50. I believe that too thin of an oil has more capillary characteristics or has a high potential that it will seep through vs thicker oil.
Like the lister above mentioned "Porsche DOES NOT recommend 0W40 oil, but only includes it on the approved list"
for model year 02 and older owner's manual, pg 170 states that:
Use only engine oils labelled as API SH or SJ, or ILSAC GF 1 and viscosity grades of SAE 10W-40 or higher.
Last edited by Carrera Mike; 01-17-2006 at 07:20 PM.
#18
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Mike, I would have to disagree with your logic. Think about your car as a human body that needs "X" to run optimally. With time comes advances in the "X" your needed for optimal performance. When that new technology is available it is wiser to move towards it since it has been shown to be more effective. There is NO reason to run 10W-40. You are selling yourself short on the low temp side but still equal on the high time side. Better protection and lube down in the lower temp range.
Like I said, I do 0W-40 and 15W-50 depending on tiem of year.
Like I said, I do 0W-40 and 15W-50 depending on tiem of year.
#19
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Originally Posted by LVDell
Is there even a fully synthetic 5W-50 on the market?
http://www.castrol.com/liveassets/bp...syntec_usa.pdf
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My two cents worth...
Experience in other older non-996 engines with some miles on them, all kinds, Porsche, Mopar, etc. shows me that switching from non-synthetic oil to Mobil 1 DOES OFTEN causes some leaking. Somehow the synthetic fits through smaller gaps easier, making gaskets and seals leak. I know this used to be a big debate, but AFAIC it's fact.
So, it would seem that a thinner grade of Mobil 1 would leak even more.
My 996 doesn't leak enough to form any droplets, but the bellhousing area isn't dry as a bone either. Running 0W-40, but considering switching. Don't know if it's ever had the RMS replaced as I got it used from a stealership with no service history.
Another question, why are people so concerned about the tiniest amount of seepage from these seals? Lots of cars do that.
(Older American iron V-8's managed with a hunk of cotton rope for a seal and didn't leak. :-) )
Bill
Experience in other older non-996 engines with some miles on them, all kinds, Porsche, Mopar, etc. shows me that switching from non-synthetic oil to Mobil 1 DOES OFTEN causes some leaking. Somehow the synthetic fits through smaller gaps easier, making gaskets and seals leak. I know this used to be a big debate, but AFAIC it's fact.
So, it would seem that a thinner grade of Mobil 1 would leak even more.
My 996 doesn't leak enough to form any droplets, but the bellhousing area isn't dry as a bone either. Running 0W-40, but considering switching. Don't know if it's ever had the RMS replaced as I got it used from a stealership with no service history.
Another question, why are people so concerned about the tiniest amount of seepage from these seals? Lots of cars do that.
(Older American iron V-8's managed with a hunk of cotton rope for a seal and didn't leak. :-) )
Bill
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Yes Syntec 5W-50 is fully synthetic.
I use Mobil 1 10W-40 which they make in Extended Performance line. http://www.mobil1.com/USA-English/Mo...ce_10W-40.aspx
I use Mobil 1 10W-40 which they make in Extended Performance line. http://www.mobil1.com/USA-English/Mo...ce_10W-40.aspx
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Originally Posted by LVDell
10W-40? You are really sacrificing protection at the lower temps in the winter during start-up. Do you run the 0W in the winter?
Point taken. Thanks, but It seldom get below 0C/32F here anyway in Chesapeake VA.
Like I said for model year 02 and older owner's manual, pg 170 states that:
Use only engine oils labelled as API SH or SJ, or ILSAC GF 1 and viscosity grades of SAE 10W-40 or higher.
If you look at the specs of 0W-40 too, it only has the "API SM/CF". Not the
API SH or SJ, or ILSAC GF 1 that is written in the manual.
#26
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I just go back to the whole "advancement in technology" argument. Either way, I honestly think it comes down to how you drive and take care of your (not specifically you) car regardless of your oil choice unless of course you are in the heat of the south/southwest during the summer (then go with the 50) or in the firgid north (then go with 0W). But for everybody in the middle, I think all these weights are fine.
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Hey Dell,
This is whats good about rennlist. We discuss for the betterment of our understanding.
Dude I agree with you on the cold start up and the 'advancement in technology' theory. No need to convince me any further. Specially if I live in Canada or North East States. But like you said, here in the middle, where I live, I favor the consistency of the shallower grade oil (like the 10W~40 than the wider 0W-40) that it provides during my high rpm runs. I put more importance to that. Somehow the engine sounds looser(more clanking) with the 0W-40 than when I have the thicker oil in it. I know that it take just a little bit more effort to push the thicker oil, but I favor the better protection(I think) it provides.
This is whats good about rennlist. We discuss for the betterment of our understanding.
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Dude I agree with you on the cold start up and the 'advancement in technology' theory. No need to convince me any further. Specially if I live in Canada or North East States. But like you said, here in the middle, where I live, I favor the consistency of the shallower grade oil (like the 10W~40 than the wider 0W-40) that it provides during my high rpm runs. I put more importance to that. Somehow the engine sounds looser(more clanking) with the 0W-40 than when I have the thicker oil in it. I know that it take just a little bit more effort to push the thicker oil, but I favor the better protection(I think) it provides.
#29
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Originally Posted by Carrera Mike
Yes Syntec 5W-50 is fully synthetic.
I use Mobil 1 10W-40 which they make in Extended Performance line. http://www.mobil1.com/USA-English/Mo...ce_10W-40.aspx
I use Mobil 1 10W-40 which they make in Extended Performance line. http://www.mobil1.com/USA-English/Mo...ce_10W-40.aspx
Actually Syntec is not synthetic. It is made from dino oil stock with some molecule ************.
It does however past the US definition for synthetic - but not the European definition. Now Mobil makes the same compound & sells it as syn in the US, they increased the price of their old syn, now call it European or super syn.
big lawsuit tween mobil & castrol