How often do you change oil

[calimedeiros]

On my 81 targa I just bought on the owners manual I think it's recomended oil change interval is 12000 Kms
How often do you guys change your motor oil ?? Is it longer periods because of our dry sump

[LakeCleElum]

My Porsches: Each year or 5,000 miles.......Since I've only put 20,000 miles on my 73.5 in the last 24 years, do it annually......

Japanese cars and motorcycles: 5,000 miles......

[Cooper911SC]

On my '81 SC every 5,000 miles.
On her 993 every 8,000 miles.

Cooper

[Bob Kontak]

Originally Posted by calimedeiros

On my 81 targa I just bought on the owners manual I think it's recomended oil change interval is 12000 Kms

See your owners manual, page 74. 15k miles/24k kilometers is the oil change interval stated.

Now, does any Porsche nut go that long, nah. I say annually and don't use thin oil. 20W50 unless you live and drive in the arctic.

[NY65912]

Annually, I never get to put on 5K a year. 20W50 Brad Penn & Mahle filter.

[calimedeiros]

Are these longer intervals because of the dry sump system or just because of how much quantity of oil we have

[Bob Kontak]

Quantity. It does not break down as quickly given the large volume.

I am not a scientist but I believe oil viscosity does not break down. Mainly the additives degrade.

[HarryD]

I am old school and do my 911 and Bus every 3,000 miles. I drive them between 3-4,000 miles a year so it is about once a year with BP 20W-50.

My 2006 and 2009 get a change every 5,000 miles with a synthetic.

[porterdog]

15k

[Ronnie's.930]

Originally Posted by HarryD

I am old school and do my 911 and Bus every 3,000 miles

No doubt the oil company executives love you for it!

[NYNick]

5000 miles with synthetic on a 996/997? Nuts

Sent from my SAMSUNG-SGH-I337 using Tapatalk

[HarryD]

RONNIES.930. No doubt they do but the way I see it, both these cars have 150,000+ miles on them and with the blow by and crap that gets into the oil, it is not about the oil but the removal of impurities in the oil is more important to me than seeing how long I could go.

On my later cars, the longer interval gives me a chAnge about every 8-10 months, so this does not seem excessive either.

If I wanted to test for longer intervals that could be a plan too but at $25-35 a test what the point any money saved on delaying the oil change is at least partially spent on testing

[HarryD]

Bob, correct it is not the oil but the additives and most importantly the ability to neutralize acids from combustion by products that gets "used up".

[Ronnie's.930]

Originally Posted by HarryD

Bob, correct it is not the oil but the additives and most importantly the ability to neutralize acids from combustion by products that gets "used up".

Harry, you could buy the cheapest, house-brand oil on the shelves at Walmart, and its additives are not going to be even touched, much less used up, in 3K miles. And if you are concerned that your high mileage engine is polluting the oil at such a rapid rate as to need 3K mileage changes, then you must be driving around with tremendously high piston ring leakage numbers, and/or your fuel system is dumping copious amounts of excess fuel into the oil. If not, those change intervals are complete lunacy.

[dicklague]

3000 to 4000 miles for me. I love my 2.7L MFI motor and have driven it 120K miles in 10 years and want to drive it for a long time.

[RSBob]

Annually

[RWebb]

oil viscosity does break down - sorta

modern multi-viscosity oils are made with long chain molecules that can coil up like springs or stretch out - when those molecules break into smaller pieces you lose the ability of the oil to change viscosity

those concerned about when to change the oil can simply get an oil analysis done

[clutch-monkey]

oil is the cheapest thing you put into an engine.. i do mine a couple of times a year (car is driven as intended though).
i'll dump it after each track day otherwise.

[RedCoupe]

Not only does it depend on how much you drive, but on where you live. When I bought my 964 ten years I was mighty surprised to find about a pint of water drain out of the oil tank before oil started to flow when I did my first oil change. I lived in the Seattle area and found that if my oil change intervals were longer than about 5,000 miles or maybe 6 months, I would get some condensation coming out with the oil. Now, living in a warmer drier climate I see no condensation whatsoever.

[weseeeee]

On my SC I change the oil once a year. I only drive it 4-5000 miles a year so it works out perfectly.