First Oil Change?

Any thoughts on when to change out the original Mobil 1 that came with the car? In the FWIW category, I already have around 5,000 miles on the original oil, so to the extent people generally change it out sooner, I'm too late for that. Thanks!

Although Porsche says synthetic oil is supposed to last around 15,000 miles, I never wait that long. For the first one, I usually have it changed around 3,000 miles, to get rid of all the break-in gunk.

I wanted to change the oil and filter at 5K miles, but the service rep dissuaded me, saying it was unnecessary. He said if I insist, he'd do it at 7500. So I did it at 7500, and plan on doing it at multiples of 7500 miles.

Thanks. Since I checked in here, my service rep also said that he wouldn't do it any earlier than 7,500 if I really wanted to.

I asked my dealership about changing the oil at 3000 miles and they told me it was not necessary and to wait till next year.

My Service Tech has a low mileage/annual oil change that they did with my 99 C4, and thats what I planned on doing with my 2003 C2...the way I see it is if the build date was in Sept of 2002, and its now October 2003, I would naturally think that its time for at least a change of OIL, if not the actual filter Your Thoughts..........?????

After the dealer declined an oil change at 7500 on my Boxster, I waited until 15,000 miles on my X50. The mechanic phoned me from the dealership and said everything was 'OK' but the oil was really dirty. He advised me to change sooner than the next scheduled change.

I bet he would, given the profit they make on it The only time I would advise an early oil change is if the car is not going to be used for quite a while (say, more than 3-4 months), of if it is a very low mileage car, in which case I would change it annually. Cheers Uwe

Once a year. It's what I do. No reason to put more money in other people's pockets. Besides, when was the last time you heard of an engine failure based on oil ( except for lack thereof)? Do yourself a favor and rigorously change coolant, brake, and pwr steering fluids - poor maintenance with them causes far more failures and greater damage than does worrying about oil. J

FWIW, I have a slightly different take. I had my oil analyzed after 2K miles on my new 02 Cab, and it showed a relatively high metallic content. That made me nervous, so I changed the oil at that point. Analyzed it again after 4K miles and the metallic content in the oil was less than half of what it was the first time, or within normal tolerances. Changed after 7500 miles. Currently have 8200 and analysis is ok. Not connected in any way with this company, but Larry Turner is good, and his company is a RENNLIST sponsor! http://members.rennlist.com/oil/ -- Test Results http://members.rennlist.com/oiluse -- Oil Consumption Data http://members.rennlist.com/webercarbs -- Weber Carb Info www.youroil.net -- Order a Oil Analysis Kits & Weber Parts!! http://members.rennlist.com/roadtest - Porsche Road Test +++

No offense, but what metallics, and why would one be "nervous"? Without an analysis at the beginning of operation, what's the baseline? J

During engine break-in, you always have a higher metal-content in the oil. Thats' completely harmless and the oil is designed to cope with it, it's precisely why the oil contains detergents (calcium sulfonates, phenates, salicyates, naphthenates), dispersants (polybutene succinimides, succinate esters) and corrosion inhibitors (zinc dithiophosphate). It does not affect the tribological properties of the oil. Oil analysis is a usful tool, but only for the automotive engineer who knows the particular engine it's applied to. To you and me (and I'm a PhD-level mechanical engineer) its' a waste of money. Cheers, Uwe

Hello All! Don told me he mentioned me on this Forum -- sorry, I don't participate in this forum much as I tend to stay with the email discussion list. Anyway, Don mentioned there was a discussion of the merits of Oil Analysis and I'll be happy to answer any questions. For anyone interested, the results of over 140 Oil Sample Tests are located at http://members.rennlist.com/oil/ In Don's case, the Silicon (Dirt) was too high at 59ppm (above around 26ppm is considered too high) and his Fuel in the Oil was too high at 6.5% by volumn (about 6% is considered high). His oil was checked at 2200 miles and the oil & filter changed at that time - the next test at 6200 miles came back with all contaminants tested in an acceptable range. Given the price of a new 911, the cost of a oil change seems a small price to pay to eliminate any high levels of contaminants. There's also a '03 GT3 in the database with a silicone level of 46. The threshold levels that the contaminates goes from being considered normal to the range where they are considered abnormal has been developed by the lab doing the testing over the past 40+ years. While testing for contaminates, the additives are also tested for - things like Calcium and Barium are used as additives. For those interested, a chart showing which contaminates indicate a wearing of which engine component/s is shown at the same Rennlist website shown above on a page titled: Element Analysis Description - you'll see things like - Boron is used as a oil additive but is also a coolant additive, so if Boron shows up in your oil sample it could be due to its use as a oil additive or (if you have tested a water cooled engine) a coolant additive which would indicate coolant getting into the oil. For people who are most interested in finding the longest an oil change can be extended without causing problems there is a test called Total Base Number (TBN) which tests for the oil's ability to neutralize the acids generated by the combustion process. Depending on the type of oil being tested, the TBN when new can be as high as 30-60. When this number falls to between 2 & 5, the oil has deteriorated to the point that the additives package can no longer eleminate the acids being generated. I hope this post isn't too long - it's a complex topic. If anyone has any questions, I'll be happy to try to help. As Don mentioned, I am a Rennlist member and sponsor. Larry '74 911

I would change the oil AT LEAST once a year, especially if you store the vehicle during the year. Change the oil before you put the car away. Don't forget to add fuel stabilizer too. My cars are getting ready for their service next weekend. Cases of oil are in the garage waiting for the transfusion. marc

Hi Larry, Thanx for posting a reply! I completely agree with your second point - if in doubt, better change the oil considering the low cost. As for the silicon levels - where does the 26ppm level come from and which engines does it apply to? You know that the M96 engine (not Turbo and GT2/3) uses a new casting technique (Lokasil) involving silicon pre-forms for the cylinders? I just wonder if that might be the reason for the high silicon content. Cheers

Hello, Thanks for your thoughts. The 26ppm was found in Don Watsons '02 996. Good idea about the casting method - they have a hard time getting all the silicone from the casting process out prior to engine assembly (from what I've read in the past) and it's entirely possible this is the source of the high level of Silicone. You said the silicone casting process isn't used in the GT2/3 engines so we'll have to look elsewhere for a source of the high silicone content in the GT3 shown in the Test Results data. Larry (74 911)

Hi: Just in case you're wondering, I mis-spoke when I mentioned metal in my oil. It was silicone just as Larry said. My concern was that the higher than normal silicone content (wherever the source) was sufficient for me to decide and change the oil. I don't see how additives would have compensated for the additional abrasiveness caused by the silicone content.

My first analysis showed 58ppm Si. The evaluation was suppossed to normal for break-in. My second at 6950 miles (first at 3265) showed 12 ppm SI. However my fuel% Vol went to 6.5 and now needs watching. I'll be doing a third analysis about the second week of November. I'll have about 10,500 miles. It's nice to be able to trend your engine.

Hi Don, basically higher silicon content does not necessarily mean abrasiveness. In order for the silicon particles to be abrasive, they have to be present in a certain granularity (size and shape) and hardness. Firstly, most oils have silicon added as an anti-foaming agent anyway. Secondly, Porsche uses Dreibond, a silicone-based sealant in its engines which also increases the silicon content of the oil, but is harmless in terms of wear (it is not harmless in terms of possibly clogging up oil lines). Thirdly, silicon could be present from the running in process of the Lokasil cylinders but would then be present in sub-critical granularity. Obviously, if silicon is present in the form of sand, that's wouldn't be so great. Cheers, Uwe

Thanks for all the info guys. Quick question: Let's say you've got a 5/03 production car and you take delivery in 10/03. And assume you only do <10k miles per year. Do you get the first oil change in 5/04 (1 year after build date) or 10/04 (one year after in service date). Remember that the car was test driven a few time between 06/03 and 10/03 probably. Thanks.

Hey guys, are you sure the factory runs synthetic during break-in? I've heard from several different sources that most manufacturers use mineral oil during their break-in periods!! I wonder why??

Well, BMWs, Porsches, and some Volkwagens come with synthetic from the factory. I'm sure other brands do, too, but those are all I can say from experience. What you are saying was the case on BMWs several years ago. BMW would recommend mineral for break-in before replacement with synthetic. But not any more.

Thanks for the advice unm, but for 20 bucks a pop I just don't want to take any chances with my car's motor....and God forbid should something happen I'll have a paper trail.