used oil analysis - 07 Box S, 7574 miles

[White987S]

Why the change?

Too many customers giving them crap about the 20k change interval?

Do the 2008 models have direct fuel injection? I've heard that people with other [non-Porsche] cars have noticed fuel diluted oil problems with this technology (at the high performance end).

Regards,

paul...

Paul, no the 987 dose not have direct fuel injection yet in the 2008 MY.

[paulv]

Why the change?

Too many customers giving them crap about the 20k change interval?

Do the 2008 models have direct fuel injection? I've heard that people with other [non-Porsche] cars have noticed fuel diluted oil problems with this technology (at the high performance end).

Regards,

paul...

Paul, no the 987 dose not have direct fuel injection yet in the 2008 MY.

OK, thanks. I don't have any other ideas of why the OCI has been reduced to 12000 miles, but I like that better than 20000 miles!!!!

Regards,

paul...

[baseball]

Regarding the change in 2008 to 12,000 maintenance intervals; Since dealerships make the most profit from their service department, perhaps they lobbied Porsche to get the service requirements increased.

[eslai]

I saw a bulletin somewhere else that showed the new intervals. They're different depending on region. Mexico has a recommended service interval of like 7500 I believe, whereas North America is at 10,000 or 12,000.

I talked to my dealership about this asking what the deal was--seems kind of shady that they wouldn't back-date those recommendations for older 987s...

[baseball]

seems kind of shady that they wouldn't back-date those recommendations for older 987s...

I agree, it just doesn't add up. Regardless I'll change my 07 987's oil every 7500 miles or so - I enjoy doing that kind of thing anyway...

[saaber]

seems kind of shady that they wouldn't back-date those recommendations for older 987s...

I agree, it just doesn't add up. Regardless I'll change my 07 987's oil every 7500 miles or so - I enjoy doing that kind of thing anyway...

Just did a used oil analysis on my 2000 S with 72k on it (posted on 986 section fyi). It has used mobil 1 0W40 since new at 15k intervals except for this last interval. This last interval was 8700 miles and the "TBN" rating was 5.2 which means there was a lot of life left in the oil. Some comments I have received say I could have doubled this oil change interval.

However the iron levels built up over time and as the report says this makes the oil more abrasive. So even though there is lots of life left in the oil and it could go 15k, the contaminants which build up in the oil warrant changing it sooner (in my opinion anyway). I like the 7500 interval as it is cheap insurance and hey, if transfusions work for tour de france racers, why not for the boxster's lifeblood? :)

Edited November 29, 2007 by saaber

[paulv]

Just did a used oil analysis on my 2000 S with 72k on it (posted on 986 section fyi). It has used mobil 1 0W40 since new at 15k intervals except for this last interval. This last interval was 8700 miles and the "TBN" rating was 5.2 which means there was a lot of life left in the oil. Some comments I have received say I could have doubled this oil change interval.

However the iron levels built up over time and as the report says this makes the oil more abrasive. So even though there is lots of life left in the oil and it could go 15k, the contaminants which build up in the oil warrant changing it sooner (in my opinion anyway). I like the 7500 interval as it is cheap insurance and hey, if transfusions work for tour de france racers, why not for the boxster's lifeblood? :)

Is this the first UOA you've done? The idea behind UOAs is to trend the data over time to see any upward changes of the wear metals which would indicate that a problem could possibly happen in the near future -- maybe the Fe level you're getting is normal -- I don't know and still on the learning curve with my Boxster and it's still being broken in. The "lot of life left in the oil" is a relative statement as the life of the oil is based on many other things (viscosity changes, fuel dilution, TBN, TAN, etc). The TBN you have only tells you that there is still a significant amount of additive (to reduce acids, etc) remaining in the oil.

You should post your UOA on BITOG so all the anti-Mobil 1 people there can heckle you -- actually, you may get some good responses.

Regards,

paul....

[cnavarro]

You should also look at getting the TBN tested too - the rule of thumb I use is when the TBN is reduced by 50% of the starting level, then it's time to change the oil. M1 0w40 starts at 10, so when you are at 5, then it's time to change IMHO. From the UOAs posted, 7,500 mi is right about that mark, like the PCA posted recommendations.

Forwarned, a bunch of us guys from the Pelican forums have had problems with Blackstone re: accuracy and repeatability of their tests. I use Staveley Services to do all my oil testing, both VOAs and UOAs.

For what its worth, there are much better approved oils than M1 0w40.

[paulv]

You should also look at getting the TBN tested too - the rule of thumb I use is when the TBN is reduced by 50% of the starting level, then it's time to change the oil. M1 0w40 starts at 10, so when you are at 5, then it's time to change IMHO. From the UOAs posted, 7,500 mi is right about that mark, like the PCA posted recommendations.

Forwarned, a bunch of us guys from the Pelican forums have had problems with Blackstone re: accuracy and repeatability of their tests. I use Staveley Services to do all my oil testing, both VOAs and UOAs.

For what its worth, there are much better approved oils than M1 0w40.

Charles,

I've also heard the 50% rule for TBN also (mainly articles from Noria publications). When did you stop using Blackstone? I've heard that they've improved on their testing.

Also, I read your "What oil should I use...." article (on the LN site) a while back and really enjoyed it -- also passed it on to a couple of my Porsche friends.

Regards,

paul....

[cnavarro]

I stopped using them beginning of this year and went back to Staveley. One of the guys over on Pelican just had very bad luck with his test and retest with Blackstone. The results with Staveley were spot on with what the manufacturer was claiming for the VOA.

[Bill_SoCal]

Hi Paul,

It was difficult to read your complete oil analysis. I see that Blackstone is recommending an oil change more frequent that 15K. Are you having your oil changed at 7,500 now?

I have a 2003 Boxster that I drove off the lot with 17 miles...I just hit 107,000 miles. I change my oil every 15K, along with a filter and air filter. I changed my main belt at 60K along with plugs...other than that, front brakes once and two sets of tires. What a great car!

Best regards,

Bill with synpsg.com

[paulv]

Hi Paul,

It was difficult to read your complete oil analysis. I see that Blackstone is recommending an oil change more frequent that 15K. Are you having your oil changed at 7,500 now?

I have a 2003 Boxster that I drove off the lot with 17 miles...I just hit 107,000 miles. I change my oil every 15K, along with a filter and air filter. I changed my main belt at 60K along with plugs...other than that, front brakes once and two sets of tires. What a great car!

Best regards,

Bill with synpsg.com

Hi Bill,

Sorry about the lousy scan -- I later realized that it's not a good idea to scan a B&W page with color settings on the scanner. I changed out the factory fill at 7500 miles and will maintain this same oil change interval. If I decided to change, I would go up to 10,000 miles and no greater I have concerns about not being able to monitor the TBN of the oil (the 2003's have a dipstick so you can draw a sample to have analyzed -- the 07's don't).

Looks like you're really enjoying your Boxster with approx 25,000 miles/year driving -- excellent!! Best wishes for the next 100,000 miles!!

Regards,

paul...

[Doug H]

Hi,

cnavarro - Charles you said this:

"For what its worth, there are much better approved oils than M1 0w40."

Can you substatiate this comment with some hard and unbiased facts please!!

Your comment about draining the engine lubricant when at 50% of the original TBN is no doubt your opinion. Most engine manufacturers state that a TBN of 1 (D4739) or 2 (D2896 - ISO 3771) is the safe minimum - or 1/3 of the virgin TBN in diesel engines!

This variance against your 50% would often represent the difference between the Porsche recommended OCI and far too early! This wastes a very valuable resource for NO benefit!!

The unreliability of UOAs is well known in Tribology circles and I suggest that trending will assist in understanding the variances and variabilty

Regards

Doug Hillary

[paulv]

.......................................

The unreliability of UOAs is well known in Tribology circles and I suggest that trending will assist in understanding the variances and variabilty

..................................

That's what I essentially do -- trying to draw conclusions from a few ppm here and a few ppm there has yielded me nothing except a headache!

Regards,

paul...

[Doug H]

Hi,

Paul you are doing the right thing. You are also correct in not focusing on a few ppm here and there - especially if lubricant Brands are changed and etc.

UOA is a complex task. To really understand the results and the implications requires much more than simply being a Lab. Technician - or a car Owner

UOA results are very hard to replicate due to such things as Operator experience, Lab equipment type and etc. and of course the level of experience and knowledge of the Analyst

With a new engine it is wise to commence a Trend database and look for the desirable downward trend in wear metal uptake along with no uptake spikes! Oil condition is important to monitor too as the experienced Analyst can perhaps detect coolant leaks and the like and the suitability of the lubricant to the engine

I have found that getting both Total Base Number (TBN), (a falling value in used oil) and Total Acid Number (TAN) (a rising number in used oil) will assist in determining your best OCI if you do not want to stick with the engine maker’s suggested interval

The PQ (Particle Quantifying) Index is a good addition to a UOA plan as it provides a real indication of the actual content of the larger and important ferrous metal wear debris

UOA is at best a very good tool for providing a “snapshot” of the lubricant’s condition. In the hands of an experienced practitioner it can provide an insight into the way an engine’s components are wearing over time and is an excellent tool in the early detection of cooling system (and some other) potential problems

Regards

Doug Hillary

Edited January 7, 2008 by Doug H