Thanks groovzila for your info of oil consumption on all three different 997s. As I said, mine seems to be between low and average oil consumption range as I needed to add about 1/3 quart to top off after 3k miles of drive during my ownership. I used same Liquid Moly High tech 5W40.
However, Still wondering which one of the three oil specs of my previous post (above) is the best for the car.

 

A few more morsels of information on this evergreen topic.

1. The electronic dip stick functions differently in the 997.1 and 997.2. In the 997.1, measurements take place with engine switched off, ideally with a cold engine, although there is an algorithm that takes oil temperature and concomitant oil expansion into account, so measurements are possible a few minutes after switching the engine off. In the 997.2, measurements take place with engine running and ideally at operating temperature. (Similar to the system used in BMW M3 cars since 2008.) Both systems have their quirks. The best strategy for the 997.1 is to measure only when cold and always in the same spot.

I've found that even small tilts of the car can change the measurement by one block (0.4l) on the display. For example, I might get a full reading with my tool box in the frunk but a 2/3 bars reading without the tool box

2. The consumer-oriented user manual states the insanely large acceptable oil consumption threshold of up to 1.5l per 1000km. On the other hand, Porsche's own workshop manual for the 997.1 quotes an acceptable consumption of only 0.5l per 1000km (ie 1 quart per 1200 miles), which is much less, and pretty much in line with common sense. See attached.

 

"Best".... oh boy.

The previous owner used only Liqui Moly oil...... just contact LiquiMoly and ask them. Tell them you miles, type of driving you do, climate.... etc. Just make sure they are Porsche A40 approved. IMO, as long as it is A40, it doesn't matter.

Peace
Bruce in Philly

 

I think the Leichtlauf High Tech is the one you want if you want to keep using that brand. I don't think you can go wrong with any good oil brand as long as you change it every year or 5000 miles. My car uses a quart every 1500 miles if I use 5W-40. I was using the Porsche recommended 0W-40 and it was going through a lot more (like a quart every 1000-1200 miles). My local indy told me the average he sees is a quart every 2K miles using 5W which he recommends here (CA). He also told me that these cars tend to "burn off the top" quickly and then stay in the middle or at one up from the bottom for a long time before needing oil.

If my indicator is at the bottom, a quart will bring it to the top.

 

I switched to the 5W-40 and did see a decrease in consumption, although I will say the digital measurement seems like it's not alway accurate, I got a low oil warning, so I checked it and it was blinking at the bottom, added a quart and re-checked later and it was near the top?

 

It is SUPER sensitive to where you are parked because the whole gauge measures like 1qt. So, my garage is tile. It will change readings depending on what tiles I park on! My lot at work will read different levels on different floors because of the slight grade changes. If I park in lots, it varies as well. Yesterday I was on a hill and it blinked at me. In my garage it has not moved since I got an oil change 2 months ago. I feel like this gauge is a little better than my experiences with TPMS but not as good as the Audi digital dipstick on my B8 Avant. At the end of the day, I was pretty satisfied with the old style dip stick.

 

Yea, I've concluded it simply sucks. I have been toying with replacing it with a new one..... very easy to do as it is right there with the oil plug. But I hear so many describe its flaky behaviour that I guess that is just the way it is.

Peace
Bruce in Philly

 

No disagreement on any of that. Here are the burn rates on my three 997's:

2006 C4S with around 40K miles: Next to no burn at all between oil changes every 10,000 miles. Maybe a quart. This one burned less oil than any of the three I've had.

2009 C4S with around 40K miles. Highest burner of the three at about a quart every 1,200 miles.

2011 GTS with 63K miles. About a quart every 2,500 miles,

If memory serves, Porsche allows for as much as a quart every 600 miles but no more. There's a member here who took European delivery of a brand new car that has burned close to that one quart every 600 miles since he took delivery. He doesn't post much anymore but last I heard he had at least 60,000 miles on the car (could have been more.......I forgot) and still the same oil burn but the car is just fine. So it seems that burning a lot of oil has no bearing on the condition of the engine. Some burn more than others for reasons nobody has explained so far, at least not that I've seen.

 

Thanks all, with this thread I got new interesting info about our cars.

 

Have 105k. Change oil evert 10k and never had to add and don’t believe any modern car needs more frequent changes and Porsche agrees. I have had zero problems with car. I do not adhere to factory recommendations for service as saw no reason to replace plugs or belt before 85k. Such service does not affect engine life. Only other service was pdk and brake flushes.

 

Very interesting. Would be nice to see some oil analysis; as many hundreds (1000s?) of posted oil analysis here have shown these engines will break down the wear packages in half that milage.

Cw

 

That will also depend on how the car is driven between oil changes, and what oil is used.

 

Not sure that's true. There is currently a large thread going right now with a spreadsheet put together to show trend data across oil brands. It's very easy to see the necessary change interval. Regarding how it's driven, I am not convinced this has anything to do with oil consumption, and there is really no scientific way to measure; outside of a long term dyno experiment. Data is anecdotal at best. My car doesn't burn oil on track. Others claim theirs does. I know for a fact, I, currently, don't have any bore issues. Perhaps others do. Some believe a quart of burned oil every 600-1000 miles is acceptable; I do not.


Cw

 

You have what you have. Luck of the draw in every case when you purchase a new or used car of any kind. Burns oil or doesn't burn oil it is what it is.

Most cars burn some oil if tracked hard for a long time. If your don't then good for you.

 

If you're buying new, I don't think it's random. Engines are not designed to burn oil, especially road going cars. Emissions standards and all.

Buying used is more of a "what you get is what you get" I agree with that.

Cw