When To Change Oil

When should you change the oil on a new 987S? The owners manual says 20,000 miles or 2 years. That seems like an aweful long time! I have always changed my oil on other new cars after the first 1,000 miles. Is this over-kill for a Porsche?

[Brucelee]

I think the first question to be answered is, how long am I likely to keep this car?

If it were me, this is how I would approach it:

If I were pretty sure I would dispose of this car within the warranty period or shortly thereafter, I would simply follow the owners manual.

If this were a long term car (however you define it) I would do the following:

1-Change the oil and filter at 1000 miles.

2-The change the oil and filter at 10K, 20K etc.

Of course, you want to use M1 and quality oil filter, pref. a M1 filter.

Good luck!

Thanks Brucelee, I agree with you. I will be a long-term keeper. But why change the oil at the 1,000 mark?

[deliriousga]

Originally Posted by bmussatti

Thanks Brucelee, I agree with you. I will be a long-term keeper. But why change the oil at the 1,000 mark?

During the break-in period your engine is "getting used to running". As the parts mesh and rub on each other, tiny pieces of metal that don't meet perfectly come off and go through the oil system. Changing the oil at 1K miles gets that stuff out of the system so it can't come loose and go through the engine again.

I'm with Brucelee on the 10K miles. I tell my wife when she hits the 10K mile marks to let me know and I change it after that, but always before the 15K mile requirement.

As for why the interval is so long, it's because it's pure synthetic from the beginning and lots of it like SD987 said. With twice the oil of the normal engine out there, it takes a lot more contaminate to dirty it up and break it down.

One thing I'd disagree with from the manual. If you put less than 7K miles/year on the car, change it annually. Sitting destroys an oil worse than driving due to moisture in the oil reacting to make it acidic as it sits.

Hey Brucelee: Is there a M1 filter for the Boxster? I've never seen one but I'd love to use those instead of the OEM.

[Brucelee]

On the question of the M1 filter for the Boxster, I have to confess that I have never purchased one (being that I am a dealer, I simply use Porsche OEM's when I do my service).

Having said that, a quick call to Mobil will inform. Sorry that I don't have this info direct.

Re: How long is the oil good for, I would disagree with the statement about the 20K miles being fine, Porsche wouldn't recommend it if it weren't fine etc.

I have seen many studies on the long term quality of syn oil and my take on it is as follows:

M1 and Amsoil start to get "tired" or dirty at around 10K miles. They CAN be refreshed by changing the oil filter at around that mark. IF you change the filter, the M1 seems to be fine until around 16-17K, when it could use another filter change or to get it out of the engine.

Frankly, to enhance the chance that my 12K dollar engine will last a goodly long time, I would simply perform an oil change and filter at 10K and not be the guy who is experimented upon.

If you buy your oil at Wally world, you pay around $40 for oil, $18 for filter. I have a guy who charges me $15 to do the change.

Cheap insurance for sure.

IMHO.

PS-the post above nails the 1000 miles change recommendation. I have seen many oil changes on cars at this mark and there are tons of metal shavings coming out. Don't want this in my long term Box for sure.

A guy at a Porsche dealer told me that they dyno the engines in Germany for 500 miles, drain the oil, and refill before shippijg to the USA. Is this true? That's why I thought you don't need to do the 1,000 change with the Boxster.

[SD987]

Old habits die hard...I too am from the school of 3000 mile oil changes but I think this approach may not be necessary in all situations.

1. If Porsche engineers felt that following a more rigorous oil change procedure would be better, they would probably recommend it. There's no financial incentive for them to increase the interval, but there certainly is for the them to decrease it, e.g. an increase in dealer service visits, improving the longetivity of the engine, thereby reducing engine failures and warrantee replacements and indirectly improving the company's reputation for reliability. If they set the intervaly at 10 or 12 thousand miles, people would still say..."wow, that's a long time"...but instead, they set it at 20,000. There's probably a great deal of thought and testing behind it.

2. Not many cars run synthetic from the get-go. I don't think that many boarders are experts on engine oil viscosity but I think we can all agree that synthetic does the job longer, it's just a question of how much longer (see point 1). We've all heard about big rig trucks that run synthetic with amazingly long intervals, and while we're not driving semis, synthetic oil is pretty amazing stuff. Conversely, I'm highly skeptical of "seasoned" pros who drain the oil and say..."wow, that's been in too long". Used oil looks alot like used oil, and irregularity such as discolored traces are indicative of other engine problems not necessarily the amount of time it's been put in service.

3. Porsche engines hold/require an amount of oil greater than the amount normally held by engines of similar displacements. Whether this translates into better lubrication is beyond my knowledge, but it certainly would infer it.

4. I think that how one drives more directly factors into oil life than months/miles elapsed. For example; driving at high revs, climate, dusty conditions, running the air conditioner alot are all variables that are difficult to quantify but definitely have an impact. Auto manufacturers attempt to determine an "average" amount of engine use (or abuse) and appropriate service intervals. Your experience will obviously vary based on your conditions, but I assume that manufacturers err in the direction of caution. Quite possibly the oil interval under ideal conditions could even be longer than it is set at.

5. IMHO people misunderstand break-in. They attribute improved "smoothness" to an "eroding" effect between moving parts, when I believe it's more accurately attributed to a "settling" effect of seals etc. Keeping in mind that the engine oil actually serves as a lubricating film that keeps parts from coming into contact with each other. The expectation that changing the oil after 1000 miles will rid the oil of particles that have eroded is unrealistic in that such particles would actually be highly undesirable, not to mention unlikely after such a short period.

But...changing the oil is only @125.00 or thereabouts, and as they say it's your money. If it gives you peace of mind, then that's a pretty small price to pay. I personally plan to get my book stamped on schedule.