Mobil 1 Diesel Oil in Porsche 996
Discussion
No doubt an expert will be along shortly to answer your question with confidence but, in the interim, here's some hearsay. 
I recall reading that there is generally little or no difference between the "petrol" and "diesel" version of a specific grade of oil from a supplier. They have to have two differently packaged versions for marketing purposes, and also so they have a better idea who they are selling to.
Therefore I'm pretty sure that your use of high quality turbo-diesel oil for a few thousand miles won't have any deleterious effects at all.
Try sending an email to opieoilman - a PH member who is in the business and knows his lubricants.
I recall reading that there is generally little or no difference between the "petrol" and "diesel" version of a specific grade of oil from a supplier. They have to have two differently packaged versions for marketing purposes, and also so they have a better idea who they are selling to.
Therefore I'm pretty sure that your use of high quality turbo-diesel oil for a few thousand miles won't have any deleterious effects at all.
Try sending an email to opieoilman - a PH member who is in the business and knows his lubricants.
The main difference between the two oils will be the content of anti-foaming/cavitation additives. Diesel oil will be designed for a much higher pressure at the bearing and a much lower rpm limit. As such, foaming and cavitation are less likely to occur.
Good job you haven't been red lining it
Seriously, unless the 2k miles have all been on track, I doubt any damage has been done.
Good job you haven't been red lining it
Seriously, unless the 2k miles have all been on track, I doubt any damage has been done.
I made a similar mistake with my Boxster and turned up for a service to OPC Guildford with Mobil 1 Diesel.
They did a bit of teeth sucking before phoning Mobil for the definitive answer. Mobil stated that it was the same oil and wouldnt cause any harm, but it was just packaged differently for marketing.
Anyway the OPC used it for the service, so I guess they must have got comfortable that there would be no engine damage.
Now safely back on the regular Mobil 1 though.
They did a bit of teeth sucking before phoning Mobil for the definitive answer. Mobil stated that it was the same oil and wouldnt cause any harm, but it was just packaged differently for marketing.
Anyway the OPC used it for the service, so I guess they must have got comfortable that there would be no engine damage.
Now safely back on the regular Mobil 1 though.
r8_1ndy said:
Ive just found out that my mechanic put mobil 1 0-W0 fully sunthetic oil in. But i thought you was supposed to put 10-w40 oil in?? Any harm caused to the engine after driving over 2000 miles or so??
I presume you mean that he put 0-W40 in rather than 10-W40? From what I understand it won't do any harm, but being a bit thinner it does increase the chances of developing oil leaks from the cam-covers (on old air-cooled clunkers like mine). Just get back to the recommended grade at the upcoming service and you'll be alright I reckon.
I would use Motul.
Mobil one is for the dealers and the likes of Halfords, I'm not even sure its a proper 100% sythetic, same goes for Castrol.
Might be worth reading this:
www.amsoil.com/performancetests/g1971/index.asp
I've used Motul, its very good, a proper synthetic, you can buy the AMS, Motul from Demon Tweeks.
Mobil one is for the dealers and the likes of Halfords, I'm not even sure its a proper 100% sythetic, same goes for Castrol.
Might be worth reading this:
www.amsoil.com/performancetests/g1971/index.asp
I've used Motul, its very good, a proper synthetic, you can buy the AMS, Motul from Demon Tweeks.
jpf40 said:
I would use Motul.
Mobil one is for the dealers and the likes of Halfords, I'm not even sure its a proper 100% sythetic, same goes for Castrol.
Might be worth reading this:
www.amsoil.com/performancetests/g1971/index.asp
I've used Motul, its very good, a proper synthetic, you can buy the AMS, Motul from Demon Tweeks.
But it was Mobil who took Shell to court because they were marketing a hydro-cracked oil as fully synthetic and undercutting Mobil 1 (which I think is the real McCoy). Read the thread with the original articles posted by Opieoilman on the subject - very interesting stuff. www.pistonheads.com/gassing/topic.asp?t=121715&f=23&h=0&hw=ester
Anyway, apart from that, I also am going to look at using Motul 8100 X-cess 5W-40 next time round because I reckon that I can get it cheap here in France. Having said that, even Mobil 1 is half price here compared to UK prices.
nel said:
I would use Motul.
Mobil one is for the dealers and the likes of Halfords, I'm not even sure its a proper 100% sythetic, same goes for Castrol.
Might be worth reading this:
<a href="www.amsoil.com/performancetests/g1971/index.asp">www.amsoil.com/performancetests/g1971/index.asp</a>
I've used Motul, its very good, a proper synthetic, you can buy the AMS, Motul from Demon Tweeks.
But it was Mobil who took Shell to court because they were marketing a hydro-cracked oil as fully synthetic and undercutting Mobil 1 (which I think is the real McCoy). Read the thread with the original articles posted by Opieoilman on the subject - very interesting stuff. www.pistonheads.com/gassing/topic.asp?t=121715&f=23&h=0&hw=ester
Anyway, apart from that, I also am going to look at using Motul 8100 X-cess 5W-40 next time round because I reckon that I can get it cheap here in France. Having said that, even Mobil 1 is half price here compared to UK prices.
I knew one of them got sued but couldn't remember which one.
I think the point here is that all the big oil giants make good oils, but they simply are no where near as good as the specialists. i.e Motul, AMS, Silkolene, Neo.
I'd agree... Either Motul 8100 or Silkolene ProS.
Its not that they are fully synthetics along with Mobil 1, its that the Motul and Silkolene are Esther based (with very high percentages of the stuff), where as the Mobil is PAO based.
Esthers create the statically charged molecules that they put in Magnatec. Magnatec has about 4% esthers. An engine oil with high Esther content will protect an unused engine with 50 microns of coating for up to 6 weeks.
Its not that they are fully synthetics along with Mobil 1, its that the Motul and Silkolene are Esther based (with very high percentages of the stuff), where as the Mobil is PAO based.
Esthers create the statically charged molecules that they put in Magnatec. Magnatec has about 4% esthers. An engine oil with high Esther content will protect an unused engine with 50 microns of coating for up to 6 weeks.
Mobil one is good oil. Opioilman, who posts here sometimes, did a good post on another forum about oil quality. Hopefully he won't mind me quoting as its nice info :
opioilman said:
Indeed, Porsche's recommendation is for 0w-40 or 5w-40 synthetic oils. They just have a deal with Mobil (or at least the Dealers do).
We have GT3's running on Silkolene PRO S 5w-40 with no issues at all.
Over M1, there are in fact positives and this oil is Porsche Approved anyway. The biggest plus is the healthy slug of ester used as basestock which Mobil1 does not have. Mobil1 is 100% poly alpha olefin and Silkolene PRO S is 80% poly alpha olefin and 20% ester.
Esters
All jet engines are lubricated with synthetic esters, and have been for 50 years, but these expensive fluids only started to appear in petrol engine oils about 20 years ago.
Thanks to their aviation origins, the types suitable for lubricants (esters also appear in perfumes; they are different!) work well from –50 degC to 200 degC, and they have a useful extra trick.
Due to their structure, ester molecules are “polar”; they stick to metal surfaces using electrostatic forces. This means that a protective layer is there at all times, even during that crucial start-up period. This helps to protect cams, gears, piston rings and valve train components, where lubrication is “boundary” rather than “hydrodynamic”, i.e. a very thin non-pressure fed film has to hold the surface apart. Even crank bearings benefit at starts, stops or when extreme shock loads upset the “hydrodynamic” film.
In the pecking order of quality, Groups I, II and III basestocks are petroleum derived, Group IV is Poly alpha olefin and Group V is ester.
Group V is the top of the tree with regards to stability and quality.
Hope this helps,
Cheers
Simon
Raven Flyer said:
Its not that they are fully synthetics along with Mobil 1, its that the Motul and Silkolene are Esther based (with very high percentages of the stuff), where as the Mobil is PAO based.
Esthers create the statically charged molecules that they put in Magnatec. Magnatec has about 4% esthers. An engine oil with high Esther content will protect an unused engine with 50 microns of coating for up to 6 weeks.
I find this info from Raven Flyer to be very interesting. I'm driving an old Porsche, 22 years old to be exact, and the car still has absolute superb "as new" oil pressure, runs great, and has only 135,000 miles on it now. It's a 1983 928. It's built well, but I also use the best oil I can find. I'm in the US and I've used Mobil-1 15W50, but have recently changed over to Amsoil, because we can order it on line and they just drop ship it to your mechanic or your office. In any case, I would NEVER let the mechanic make the choice for my oil. Since I usually change the oil myself, and drop the old stuff off at a marina where they collect used oil, I don't normally have that problem. If one of my cars is in the shop and they have to go in for work that suggests oil should be changed, I'm always very very concerned that they would dump in something of less quality than I would.
One good thing about the Amsoil site, is the fact that they publish all of their specs. You can see the difference between diesel specific oil and oil intended for an automobile turbocharger, and there is a big difference. I don't think there would be "damage done" using a diesel specific oil, but I'd change it out.
Furthermore, I would always refer to the owners manual, and NOT listen to the mechanics. Many of those guys repeat "heresay" and the owners manual pretty well spells it out. For instance, look at this one printed in 1983
If you haven't already seen enough references about synthetic oil, well, you can indulge yourself with this one but don't try holding your breath when you read it! www.network54.com/Forum/message?forumid=426130&messageid=1125341697
Regards, Dogsharks
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