oil change
#1
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I know that Porsche recommends oil change at 15k miles, but I have always been a fanatic about changing oil often on my cars. I have 3500 miles on my TT and am thinking it might be a good idea to put in fresh synthetic and new filter, but don't want to waste the money if it it doesn't make sense. Any advice???
#2
Burning Brakes
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I think it makes sense though probably I would wait just a little longer. This is especially true if you are in N.A. where oil is cheap.
Note though that even if you drain the engine, header tank and two turbos you will still only get half of the oil out of the system.
Do some searching. There has been lots of discussion of this issue on the various forums.
S.
Note though that even if you drain the engine, header tank and two turbos you will still only get half of the oil out of the system.
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Do some searching. There has been lots of discussion of this issue on the various forums.
S.
#3
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change your engine oil at manufacturer reccomended intervals. places like jiffi lube will reccomend every 3k or 4 months, porsche will reccomend 1 year on most vehicles... the reason for this is because in germany a car must be inspected every year and demonstrate proof of an oil chance within the past 12 months.
chances are, even if the car is driven hard, as long as a good quality synthetic is used you can easially go 1 year between changes.
What to look for in an oil in a turbo charged car boils down to flash point, ash, and zinc. the flash point is the vapor point of the oil, or the hottest it will remain liquid. oils such as mobil 1 have flash points around 300-400 degrees (F). the best oil flash point i've found on the market is red line, which is around 500 degrees.
ash is the ash content remaining when the oil flashes, thus what is left to dirty and clog your filter, oil channels, and bearings. ash contents on all modern oils are quite low, although i would reccomend staying away from "race" oils such as quaker state's race oil (the name eludes me right now). i believe it's ash content is double or so the amount in most other oils... high ash content is one way to raise the flash point, among other benefits (this doesnt mean that a high flash point means a high ash content).
the last thing to look for is the zinc content. usually between .005 and .015% (i believe), the higher the zinc content the better the oil will protect against metal hitting metal. while this should happen infrequently in modern engines, it will happen most often in turbocharged cars... turbo's would use gear oil if they could.
anyway, zinc acts as a polish when metal hits metal. it gets used up but prevents serious rough surfaces, and thus more metal contact.
anyway, mobil 1 is an excellent oil in most of these repects. a high zinc content, low ash content, and medeocre flash point combine on a daily driver for an oil that doesnt need to be changed more often then porsche reccomends.
a caveat is that if you hear clicking sounds for a few seconds coming from your head after it's been sitting then chances are the oil cut off valve in your filter is gone. this valve will keep oil in the filter and in the head (somewhat) so when the car is started the head never starves for oil. while this isnt the end of the world, if this happens chances are you should change the oil with the filter.
finally, to check and see if you need an oil change empirically pull out the dip stick just after shutting off the car (it will be hot). now, run your finger in the oil on the stick going up to the top of the stick (to smooth out the oil and make it a thinner layer). if the oil has alot of metal flakes (some flaking is normal), or is a very off color, change your oil. this is the best method to see if you need a change, as intervals really mean nothing with synthetic oils because it will boil down to how the car is driven (dino oils can become acidic over time, around 6-8 months; polymer oils will usually never go acidic).
hope this help,
Cheers,
chances are, even if the car is driven hard, as long as a good quality synthetic is used you can easially go 1 year between changes.
What to look for in an oil in a turbo charged car boils down to flash point, ash, and zinc. the flash point is the vapor point of the oil, or the hottest it will remain liquid. oils such as mobil 1 have flash points around 300-400 degrees (F). the best oil flash point i've found on the market is red line, which is around 500 degrees.
ash is the ash content remaining when the oil flashes, thus what is left to dirty and clog your filter, oil channels, and bearings. ash contents on all modern oils are quite low, although i would reccomend staying away from "race" oils such as quaker state's race oil (the name eludes me right now). i believe it's ash content is double or so the amount in most other oils... high ash content is one way to raise the flash point, among other benefits (this doesnt mean that a high flash point means a high ash content).
the last thing to look for is the zinc content. usually between .005 and .015% (i believe), the higher the zinc content the better the oil will protect against metal hitting metal. while this should happen infrequently in modern engines, it will happen most often in turbocharged cars... turbo's would use gear oil if they could.
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
anyway, zinc acts as a polish when metal hits metal. it gets used up but prevents serious rough surfaces, and thus more metal contact.
anyway, mobil 1 is an excellent oil in most of these repects. a high zinc content, low ash content, and medeocre flash point combine on a daily driver for an oil that doesnt need to be changed more often then porsche reccomends.
a caveat is that if you hear clicking sounds for a few seconds coming from your head after it's been sitting then chances are the oil cut off valve in your filter is gone. this valve will keep oil in the filter and in the head (somewhat) so when the car is started the head never starves for oil. while this isnt the end of the world, if this happens chances are you should change the oil with the filter.
finally, to check and see if you need an oil change empirically pull out the dip stick just after shutting off the car (it will be hot). now, run your finger in the oil on the stick going up to the top of the stick (to smooth out the oil and make it a thinner layer). if the oil has alot of metal flakes (some flaking is normal), or is a very off color, change your oil. this is the best method to see if you need a change, as intervals really mean nothing with synthetic oils because it will boil down to how the car is driven (dino oils can become acidic over time, around 6-8 months; polymer oils will usually never go acidic).
hope this help,
Cheers,