Recommended oil viscosity?
#16
Administrator - "Tyson"
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Consult the owners manual - find the viscosity which matches the average ambient temperature you plan on using your car.
The "high ZDDP" is grossly misunderstood. You want an oil that has the old standard prior to about 2002 or so which is 1100/1200ppm ZDDP. Almost every 15/20w-50 oil meets this. More difficult to find thinner oils with this level.
There are oils on the market with more ZDDP (like the air cooled motorcycle stuff) and more is not necessarily better. Stick with the "standard" for which these cars were designed, don't over do it.
Also, don't just dump in some ZDDP additive "just to be safe" - use a proper oil from the get go.
I've come across a number of 16V cars that have been running 5w-40 their whole life (like my 1980 with over 80k on the odo). I have yet to drive the car on a really hot day to report on what the oil pressure does. My 1981 threw a lifter clacking hissy fit when I tried 5w-40 many years ago.
There are oils on the market with more ZDDP (like the air cooled motorcycle stuff) and more is not necessarily better. Stick with the "standard" for which these cars were designed, don't over do it.
Also, don't just dump in some ZDDP additive "just to be safe" - use a proper oil from the get go.
I've come across a number of 16V cars that have been running 5w-40 their whole life (like my 1980 with over 80k on the odo). I have yet to drive the car on a really hot day to report on what the oil pressure does. My 1981 threw a lifter clacking hissy fit when I tried 5w-40 many years ago.
#17
I've come across a number of 16V cars that have been running 5w-40 their whole life (like my 1980 with over 80k on the odo). I have yet to drive the car on a really hot day to report on what the oil pressure does. My 1981 threw a lifter clacking hissy fit when I tried 5w-40 many years ago.
#18
Rennlist Member
Thread Starter
Randy, thanks for changing to "Canuckland"
Unless you were jokingly referring to the former Canadian Forces base in Kandahar, the term "Canuckistan" could be considered highly offensive. I'm confident this wasn't your intention.
Best,
Unless you were jokingly referring to the former Canadian Forces base in Kandahar, the term "Canuckistan" could be considered highly offensive. I'm confident this wasn't your intention.
Best,
#19
Rennlist Member
Thread Starter
Unless you were jokingly referring to the former Canadian Forces base at Kandahar, the term "Canuckistan" could be considered highly offensive. I'm confident that wasn't your intention.
Best,
#21
Administrator - "Tyson"
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Yea, not sure I would have attempted my experiment on the 81 in Texas. Around here, 90% of the time 5w-40 will work fine but that one week with average temps in the high 90's park the car or just use 15w-50 in the summer.....
#22
Yeppers, I agree. I recommend the higher stuff for the Northern areas for the ZDDP content and you aren't going to be hurting anything anyway by using it. Better safe than stupid.
#23
Rennlist Member
Thread Starter
Porsche is now marketing an oil for "classic cars". You might want that if you need the Porsche brand. Otherwise, the weight of the oil differed based on the climate where the car was being shipped. (At least, that's what I've been told.) The recommended oil weights, based on ambient temps, are found in the owner's manual.
#24
Rennlist Member
Thread Starter
Consult the owners manual - find the viscosity which matches the average ambient temperature you plan on using your car.
The "high ZDDP" is grossly misunderstood. You want an oil that has the old standard prior to about 2002 or so which is 1100/1200ppm ZDDP. Almost every 15/20w-50 oil meets this. More difficult to find thinner oils with this level.
There are oils on the market with more ZDDP (like the air cooled motorcycle stuff) and more is not necessarily better. Stick with the "standard" for which these cars were designed, don't over do it.
Also, don't just dump in some ZDDP additive "just to be safe" - use a proper oil from the get go.
I've come across a number of 16V cars that have been running 5w-40 their whole life (like my 1980 with over 80k on the odo). I have yet to drive the car on a really hot day to report on what the oil pressure does. My 1981 threw a lifter clacking hissy fit when I tried 5w-40 many years ago.
The "high ZDDP" is grossly misunderstood. You want an oil that has the old standard prior to about 2002 or so which is 1100/1200ppm ZDDP. Almost every 15/20w-50 oil meets this. More difficult to find thinner oils with this level.
There are oils on the market with more ZDDP (like the air cooled motorcycle stuff) and more is not necessarily better. Stick with the "standard" for which these cars were designed, don't over do it.
Also, don't just dump in some ZDDP additive "just to be safe" - use a proper oil from the get go.
I've come across a number of 16V cars that have been running 5w-40 their whole life (like my 1980 with over 80k on the odo). I have yet to drive the car on a really hot day to report on what the oil pressure does. My 1981 threw a lifter clacking hissy fit when I tried 5w-40 many years ago.
#25
Pro
I see you're from Ontario so I'd hazard a guess you get summer/winter temperature extremes. For freezing and below, especially if your car is getting that cold most of the time, use a 5W-something. Otherwise use a 10 or 15W-something. In Texas, use a 20W-something.
The 'something' is either 40 or 50, and you won't do any harm with a 50, as most owners will tell you.
Let the oil pressure gauge guide you: should be up to pressure almost as soon as the engine fires, and be showing 5 Bar until the oil warms. When hot, should show 2-3 Bar at idle, and 4-5 Bar at 2000rpm, and 5 Bar over 2500 rpm. (In the WSM somewhere).
Re ZDDP: All xW-40 weight oils and heavier have a minimum of 800ppm. I prefer 1000ppm+ (just cos it's a middle of the range number). And, yes, you can have too much ZDDP, to such an extent that enough of the molecules can coat the metal surface and interfere with the oil film lubrication dynamics. So use a level of ZDDP appropriate for the engine design.
#26
Administrator - "Tyson"
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Or you can just do what Kibort does.....
#27
Rennlist Member
if you want to be safe, use the 20-50..... Unless you are in a extreme cold area.
and if you want to race it, lose the mobil 1, it breaks down so much that the oil pressure light will come on at the track.... use a redline or amsoil equiv if possible if you visit the track. NEVER run the track with a mobil 1 oil.
#28
Shameful Thread Killer
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Rennlist Member
Opening a can of worms with this one, everyone has their preferences. The general Rennlist consensus over the years seems to be Mobil 1 15W-50 and it is what I've used on my 928 DD for the past 7+ years.
The Shell Rotella 15W-40 is a dino oil, not synthetic. As dino oils go, Rotella 15W-40 is very good.
That said, I tend to follow to crowd with this one and have been very happy with Mobil 1 15W-50. Lots of opinions out there though.
The Shell Rotella 15W-40 is a dino oil, not synthetic. As dino oils go, Rotella 15W-40 is very good.
That said, I tend to follow to crowd with this one and have been very happy with Mobil 1 15W-50. Lots of opinions out there though.
YMMV, but once more - they are all dino oils.
#29
Team Owner
I would suggest to use Valvoline VR1 racing oil 20 W 50, good on the zinc count and never any issues with viscosity breakdown available at most FLAPS
#30
Rennlist Member
Trouble with the VR1 (my oil of choice) is that it has been outlawed in California and production has been stopped (what I have been told by every parts store I have visited).
Just stick with a good 15 or 20W 50 and you will be fine.
Just stick with a good 15 or 20W 50 and you will be fine.