996 GT3 oil reccomendations
Discussion
Hi all,
The PH search function still isn’t working. I am looking for a recommendation please for an oil for a 996GT3 that does a lot of trackday work.
I have looked at my invoice from JZM and they used Edge 10w/60, which seemed high but I suppose offers the best protection under higher workloads?
There seems to be a few good varieties in this weight:
Silkolene Pro S/Fuchs Titan Race Pro S – an ester synthetic oil
Castrol Edge – seems to be 2, TWS (for BMW M’s), and a Sport. Both fully synthetic
Mobil 1 – extended life
Many thanks,
BJ
The PH search function still isn’t working. I am looking for a recommendation please for an oil for a 996GT3 that does a lot of trackday work.
I have looked at my invoice from JZM and they used Edge 10w/60, which seemed high but I suppose offers the best protection under higher workloads?
There seems to be a few good varieties in this weight:
Silkolene Pro S/Fuchs Titan Race Pro S – an ester synthetic oil
Castrol Edge – seems to be 2, TWS (for BMW M’s), and a Sport. Both fully synthetic
Mobil 1 – extended life
Many thanks,
BJ
Mobil 1 Extended life. 10W/60W
Top quality motorsport oil.
You have to remember the GT3 block is derived from the 964R engine which always used thicker oils than the current trend for low viscosity 0W/30W oils. These provide rapid lubrication on start up and may marginally improve fuel consumption due to lower frictional losses, but IMHO are much less robust in a hot engine.
I use 10W/60W in my GT3 but always make sure its properly warm before giving it any beans. It also tends to use no oil between changes after 65K miles so something must be working well!
Top quality motorsport oil.
You have to remember the GT3 block is derived from the 964R engine which always used thicker oils than the current trend for low viscosity 0W/30W oils. These provide rapid lubrication on start up and may marginally improve fuel consumption due to lower frictional losses, but IMHO are much less robust in a hot engine.
I use 10W/60W in my GT3 but always make sure its properly warm before giving it any beans. It also tends to use no oil between changes after 65K miles so something must be working well!
At the risk of sticking my head right into the middle a bear trap....
I'm not sure you want to be up as high as 10W-60.
Running the higher oil makes sense in a car that only sees track use, doesn't have repeated start ups etc but even in those circumstances that seems quite a leap given UK air temps. Even on a warm day it's not that hot here.
I'd have though 5w-50 would have been a better bet as you get to cover the start up base and the track engine running base too.
I thought current thinking was nothing resembling "extended life" oils anywhere near a performance engine.
I don't know squat about oils and I suspect while everyone has opinions no one else does much either. You need to find folk who are trying all sorts and doing used oil analysis and see what their feed back is.
Cup engine data isn't of use as drive cycle differs massively and there is no variocam.
I'm not sure you want to be up as high as 10W-60.
Running the higher oil makes sense in a car that only sees track use, doesn't have repeated start ups etc but even in those circumstances that seems quite a leap given UK air temps. Even on a warm day it's not that hot here.
I'd have though 5w-50 would have been a better bet as you get to cover the start up base and the track engine running base too.
I thought current thinking was nothing resembling "extended life" oils anywhere near a performance engine.
I don't know squat about oils and I suspect while everyone has opinions no one else does much either. You need to find folk who are trying all sorts and doing used oil analysis and see what their feed back is.
Cup engine data isn't of use as drive cycle differs massively and there is no variocam.
Edited by fioran0 on Wednesday 14th March 20:17
Thanks guys, I might err on the side of caution and keep the 10w/60.
I havent heard about these extended life oils and performnace issues but that does sound worrying. I might email that oilman chap on here, I think he works for opieoils and was offering free oil reccoemndations a while back.
I havent heard about these extended life oils and performnace issues but that does sound worrying. I might email that oilman chap on here, I think he works for opieoils and was offering free oil reccoemndations a while back.
BrendonJ said:
Hi all,
The PH search function still isnt working. I am looking for a recommendation please for an oil for a 996GT3 that does a lot of trackday work.
I have looked at my invoice from JZM and they used Edge 10w/60, which seemed high but I suppose offers the best protection under higher workloads?
There seems to be a few good varieties in this weight:
Silkolene Pro S/Fuchs Titan Race Pro S an ester synthetic oil
Castrol Edge seems to be 2, TWS (for BMW Ms), and a Sport. Both fully synthetic
Mobil 1 extended life
Many thanks,
BJ
You have to be careful. Just picking an oil because its hot viscosity is high is not a good reason to pick an oil.The PH search function still isnt working. I am looking for a recommendation please for an oil for a 996GT3 that does a lot of trackday work.
I have looked at my invoice from JZM and they used Edge 10w/60, which seemed high but I suppose offers the best protection under higher workloads?
There seems to be a few good varieties in this weight:
Silkolene Pro S/Fuchs Titan Race Pro S an ester synthetic oil
Castrol Edge seems to be 2, TWS (for BMW Ms), and a Sport. Both fully synthetic
Mobil 1 extended life
Many thanks,
BJ
No 10w40, 10w-50 or 10w60 oil is on Porsche's approved oils list. There are a few 0w-40 oils, many 5w-40 oils, and one 5w-50 (Mobil 1). Some of the 5w-40 oils are Group V (ester based)and are reported to be very good oils.
Using too heavy an oil can actually cause problems. A heavier oil generates more heat from hydraulic friction and an engine running a heavier oil can actually experience higher oil temps at the bearing interfaces than an engine running a lighter oil.
Also, I believe in the case of this engine its camshaft to lifter bucket interfaces are splashed lubed by the oil that comes from out/around the lifter bucket. A heaver oil might result in diminished oil flow from around this bucket (the clearances between the bucket and the bore in which it is in are very very close) and a different splash characteristic that results in less then optimum lubrication of this very critical interface.
It is your car and your engine of course and you can run any oil you choose, but there are many cars running one of the approved oils and they do not seem to be having any problems.
A move to a 10w-60 oil seems an attempt to fix something that doesn't appear to be broken.
Sincerely,
Rockster.
I've run my 996 GT3 on 15W50 and latterly 10W60 Mobil-1 exclusively since purchase with 20K miles on it 4 years ago. The car does around 25 trackdays a year & gets an oil and filter change every 4K miles. It's used all year round & lives outside. It never does short journeys & is always properly warmed before giving it the beans.
It was stripped for a rebuild at the start of the year, not because there was anything wrong with it, but because it's a keeper & I've done 100 trackdays & about 20,000 track miles in it. I'm a believer in preventing disaster if possible, so it seemed prudent to do a rebuild to ensure the next 4 years would be equally trouble-free. The total mileage was 84,500 at the strip. Leakdown measured 1-2% on all bores & the crank measured zero wear and was simply polished prior to the rebuild. The only real signs of wear were the valve guides & seats.
It was stripped for a rebuild at the start of the year, not because there was anything wrong with it, but because it's a keeper & I've done 100 trackdays & about 20,000 track miles in it. I'm a believer in preventing disaster if possible, so it seemed prudent to do a rebuild to ensure the next 4 years would be equally trouble-free. The total mileage was 84,500 at the strip. Leakdown measured 1-2% on all bores & the crank measured zero wear and was simply polished prior to the rebuild. The only real signs of wear were the valve guides & seats.
nxi20 said:
I've run my 996 GT3 on 15W50 and latterly 10W60 Mobil-1 exclusively since purchase with 20K miles on it 4 years ago. The car does around 25 trackdays a year & gets an oil and filter change every 4K miles. It's used all year round & lives outside. It never does short journeys & is always properly warmed before giving it the beans.
It was stripped for a rebuild at the start of the year, not because there was anything wrong with it, but because it's a keeper & I've done 100 trackdays & about 20,000 track miles in it. I'm a believer in preventing disaster if possible, so it seemed prudent to do a rebuild to ensure the next 4 years would be equally trouble-free. The total mileage was 84,500 at the strip. Leakdown measured 1-2% on all bores & the crank measured zero wear and was simply polished prior to the rebuild. The only real signs of wear were the valve guides & seats.
Your recommendation, and others like your's, is kind of like a 90 year smoker advising everyone to take up smoking because hey he's smoked for nearly 90 years.It was stripped for a rebuild at the start of the year, not because there was anything wrong with it, but because it's a keeper & I've done 100 trackdays & about 20,000 track miles in it. I'm a believer in preventing disaster if possible, so it seemed prudent to do a rebuild to ensure the next 4 years would be equally trouble-free. The total mileage was 84,500 at the strip. Leakdown measured 1-2% on all bores & the crank measured zero wear and was simply polished prior to the rebuild. The only real signs of wear were the valve guides & seats.
IOWs you arrived at where you are with your car and your engine using the oil you did by luck and you expect everyone else to have the same good luck as you have had?
Well, maybe they will. But maybe they won't.
Me I prefer to play the odds and run an oil the makers of the engine recommend not some oil a handful of lucky owners and indy shops recommend.
BTW, I won't list all the oils some USA owners run and indy shops in the USA advise their customers to run, but 10w-60 is not mentioned very often. 10w-40 or 15w-50 oils appears to be as far off the oil reservation as USA shops are willing to go, save for one or two that believe it or not actually recommend Mobil 1 0w-40 oil. Seems the recommended oils is all over the map oil wise.
Apparently that there was a good 10w-60 weight oil available that bettered the other oils Porsche has listed on its approved oils list clearly was overlooked by Porsche who found just about every good 0w-40 and 5w-40 and 5w-50 oil in the world. Guess Porsche can't count above 5w-50.
Sincerely,
Rockster.
You should be using the thinnest oil that still gives the required oil pressure at operating temp.
In an engine, oil pressure and oil flow are pretty much inversely related. Thick gloopy oil gives high pressure but not great flow. Nice high oil pressure numbers are very soothing, but don't really say anything about how well the engine is being lubricated. And it's flow that determines how well an engine is being lubricated, and not pressure.
As Rockster has said, go with Porsche's recommendation. They might just know more about the requirements of their engines than anybody else.
In an engine, oil pressure and oil flow are pretty much inversely related. Thick gloopy oil gives high pressure but not great flow. Nice high oil pressure numbers are very soothing, but don't really say anything about how well the engine is being lubricated. And it's flow that determines how well an engine is being lubricated, and not pressure.
As Rockster has said, go with Porsche's recommendation. They might just know more about the requirements of their engines than anybody else.
Finally.... Some sense outs 
Without used oil analysis and good data logging of engine data you quite simply have no idea what your oil is doing. Unless you are going to invest in this to track changes you make and get all oil analysed how do you know that your change is improving things and that the oem spec wasn't optimal? You don't. Infact how do you even know what you are looking to improve?
Even without doing any tests, 10w-60 will be thicker than you want at start up (and thicker than a 0w) and thicker than recommended at operating temp. You actually won't ever be at the specified correct viscosity.
Without any specific and clear data showing why in your circumstances you need this increased viscosity, what exactly wasnt being achieved with 0w-40 and how 10w-60 provided the solution, I can't see why one would go this route.
Without used oil analysis and good data logging of engine data you quite simply have no idea what your oil is doing. Unless you are going to invest in this to track changes you make and get all oil analysed how do you know that your change is improving things and that the oem spec wasn't optimal? You don't. Infact how do you even know what you are looking to improve?
Even without doing any tests, 10w-60 will be thicker than you want at start up (and thicker than a 0w) and thicker than recommended at operating temp. You actually won't ever be at the specified correct viscosity.
Without any specific and clear data showing why in your circumstances you need this increased viscosity, what exactly wasnt being achieved with 0w-40 and how 10w-60 provided the solution, I can't see why one would go this route.
Edited by fioran0 on Tuesday 20th March 12:09
Rockster said:
Your recommendation, and others like your's, is kind of like a 90 year smoker advising everyone to take up smoking because hey he's smoked for nearly 90 years.
Hardly. Perhaps you'd like to point me to where exactly I recommend that anyone use anything?
All I posted was my direct experience of using a thicker oil than the one recommended by Porsche. I find it rather odd that people believe that only the "recommended" oil is suitable for every conceivable application. In much the same way as the default engine map isn't optimised for running on high quality fuel because the car is sold all over the world and will encounter poor quality fuel. If I was using the car for short journeys and road work, rather than track work, I'd use a different oil.
The OP specifically mentioned heavily tracking his car. I think my car falls into that category and it appears from direct evidence obtained during a stripdown that wear was minimal using thicker oil and so I thought that would be of interest to PHers with GT3s with fewer miles than mine & a penchant for tracking them. Nowhere do I claim that using the recommended oil wouldn't have produced exactly the same results, but I can't know that as I can only go on the evidence I have. You, on the other hand, have a touching faith that Porsche are all-knowing and that straying from the approved list is in some undefined way, dangerous. I am presenting evidence that counters that idea & you seem to have an ill-defined problem with that without actually presenting evidence of your own beyond blind faith that "Porsche knows best". Hey ho, each to their own...
What anyone decides to do as a result of my observations is obviously entirely up to them.
Except from what I read, you only have latterly ran 10w-60 so cannot know it's contribution to wear. had it caused all the wear discovered at rebuild, had it stopped it entirely or began to cause it at an increased rate etc.
I've also not seen you present a view on what you were addressing with the change to 10w-60 and info on if this has now changed.
We're you seeing pressure,flow,temp variations on track use at high revs that were troubling or indicating what was in before was incapable?
Without a clear concept of what you were looking to achieve with an oil spec change it raises more questions than it gives info to those on the outside (well myself atleast), especially since it flies in the opposite direction to conventional oil theory. if it was simply a case of doing trackdays and feeling that thicker would be better then thats your choice entirely. you are entitled to make whatever you feel best suits your car. we will all move on but if theres more to it then i for sure would like to hear about it. im not looking to poke fun, im genuinely always looking to expand my knowledge base.
At the moment you aren't presenting much more than a preference for ice cream flavour and feedback that you think it tastes yum. the engine wear rates measured at tear down are meaningless given you mostly ran on something else. All that can be said for sure is that it didn't make things go kaput in the time you had it in there, in the circumstances you used it in. if you only run on 10w-60 going forwards, then next tear down will give accurate feedback on 10w-60 in relation to engine internals/wear however.
I'm not saying you are wrong in your selection, simply that as things stand there's nothing you've said gives any indication that your change has been beneficial in a general sense or was carried out in response to an identified issue that has now been solved. im keen to hear more as it would be good to move you from simply a statistic (a guy with 10w-60 in his engine!!!!!) to learning something from your experience.
997 cup, full motec data logging, used oil analysis, most testing/practice/qual/races carried out in 100degF+ air temp and there was never any indication I needed 10w-60 in there. A track day car that should be more sensitive to viscosity, by way of using variocam, running under less stress using such a heavy oil is therefor interesting to hear about.
BTW how did you manage a 1-2% leak down test with worn valve seats and stem seals?
I've also not seen you present a view on what you were addressing with the change to 10w-60 and info on if this has now changed.
We're you seeing pressure,flow,temp variations on track use at high revs that were troubling or indicating what was in before was incapable?
Without a clear concept of what you were looking to achieve with an oil spec change it raises more questions than it gives info to those on the outside (well myself atleast), especially since it flies in the opposite direction to conventional oil theory. if it was simply a case of doing trackdays and feeling that thicker would be better then thats your choice entirely. you are entitled to make whatever you feel best suits your car. we will all move on but if theres more to it then i for sure would like to hear about it. im not looking to poke fun, im genuinely always looking to expand my knowledge base.
At the moment you aren't presenting much more than a preference for ice cream flavour and feedback that you think it tastes yum. the engine wear rates measured at tear down are meaningless given you mostly ran on something else. All that can be said for sure is that it didn't make things go kaput in the time you had it in there, in the circumstances you used it in. if you only run on 10w-60 going forwards, then next tear down will give accurate feedback on 10w-60 in relation to engine internals/wear however.
I'm not saying you are wrong in your selection, simply that as things stand there's nothing you've said gives any indication that your change has been beneficial in a general sense or was carried out in response to an identified issue that has now been solved. im keen to hear more as it would be good to move you from simply a statistic (a guy with 10w-60 in his engine!!!!!) to learning something from your experience.
997 cup, full motec data logging, used oil analysis, most testing/practice/qual/races carried out in 100degF+ air temp and there was never any indication I needed 10w-60 in there. A track day car that should be more sensitive to viscosity, by way of using variocam, running under less stress using such a heavy oil is therefor interesting to hear about.
BTW how did you manage a 1-2% leak down test with worn valve seats and stem seals?
Edited by fioran0 on Wednesday 21st March 18:08
had a chance to sit down and thought id post the viscosities of some oils for folks to look at.
Mobil1 0w-40:...................78.3cSt@40c, 14.0cSt@100c
Shell Helix Ultra 0w-40:......75.2cSt@40c, 13.6cSt@100c
Shell Helix Ultra 5w-40:......74.4cSt@40c, 13.1cSt@100c
Mobil1 10w-60:................152.7cSt@40c, 22.7cSt@100c
Castrol Edge 10w-60:........173.0cSt@40c, 22.7cSt@100c
from this list, mobil1 0w-40 and helix 5w-40 are on the porsche recommended list, so its safe to assume this is the viscosity levels they think their engines need.
looking over the data, shells 0w-40 is thinner than mobils 0w-40, but shells 5w-40 is thinner still than both 0w-40 oils.
the thinnest 10w-60 (mobil1) is 62% thicker at operating temps than the mobil1 0w-40 and 73% thicker than the helix 5w-40 at operating temp.
at temps a little after startup the 10w-60 oils are off the chart in terms of their thickness by comparison.
As I understand it, educated oil thinking is that optimal is a value of about 10cSt at operating temp on modern engines, so it not only looks like porsche, inline with most manufacturers specify a decent "safety" margin in terms of their recommended viscosity for their road cars but that by pushing it out to a 10w-60 you are going significantly further away.
edit to add:
any UOA ive seen on mobil1 0w-40 suggests that it shears down pretty quickly so its initial thickness at operating temp over helix 5w-40 is balanced out fairly rapidly.
Mobil1 0w-40:...................78.3cSt@40c, 14.0cSt@100c
Shell Helix Ultra 0w-40:......75.2cSt@40c, 13.6cSt@100c
Shell Helix Ultra 5w-40:......74.4cSt@40c, 13.1cSt@100c
Mobil1 10w-60:................152.7cSt@40c, 22.7cSt@100c
Castrol Edge 10w-60:........173.0cSt@40c, 22.7cSt@100c
from this list, mobil1 0w-40 and helix 5w-40 are on the porsche recommended list, so its safe to assume this is the viscosity levels they think their engines need.
looking over the data, shells 0w-40 is thinner than mobils 0w-40, but shells 5w-40 is thinner still than both 0w-40 oils.
the thinnest 10w-60 (mobil1) is 62% thicker at operating temps than the mobil1 0w-40 and 73% thicker than the helix 5w-40 at operating temp.
at temps a little after startup the 10w-60 oils are off the chart in terms of their thickness by comparison.
As I understand it, educated oil thinking is that optimal is a value of about 10cSt at operating temp on modern engines, so it not only looks like porsche, inline with most manufacturers specify a decent "safety" margin in terms of their recommended viscosity for their road cars but that by pushing it out to a 10w-60 you are going significantly further away.
edit to add:
any UOA ive seen on mobil1 0w-40 suggests that it shears down pretty quickly so its initial thickness at operating temp over helix 5w-40 is balanced out fairly rapidly.
Edited by fioran0 on Wednesday 21st March 19:19
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