Castrol oil branding / grades USA v UK - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Greetings all Having scoured the forum, it seems Castrol Syntec 10W40 would be the preferred oil for my 2.5. However, I can't find much reference to this oil in the UK it certainly does not appear on Castrol's UK website. I also note that on the USA site, there is no longer a Syntec oil, rather there is "Castrol Edge with Syntec Power technology". There are Castrol Edge oils in the UK - Castrol Edge and Castrol Edge Sport. But neither is available in 10W40. Closest is 0W40. Any ideas whether this is just a branding issue / are there differences in the way oil grades are rated either side of the pond?

From what I have been able to research, Castrol Edge is supposed to be the next generation and a step up from Syntec. A better oil. Where I live I have only been able to find "Edge" in 5-30 and 10-30 weights. Because both of my Boxsters are older (98 with 132k miles & 2K with 52k miles) I'm staying with the 10-40 weight.

Thanks. May I ask what you use?

It seems to me this is all brought on by the never ending quest for reduced emissions & increased fuel economy regardless of the impact on engine wear. In the USA it seems Castrol is seperating the new oils into emissions compliant & "specially formulated for classic cars" with the most obvious difference is removing zinc & lower viscositys for cars with cataylitic converters. I believe 10-40 is the best viscosity for 40 degree & warmer M96 engine operation. Castrol is owned by BP so maybe you could pop into their office & tell them what we want for oil along with resonably priced higher octane petrol!

We've had Castrol Edge packaged oils here in Australia for about 4 years now - but like you guys in the UK / US there is no *W40 grade available. I have used Castrol lubricants in my bikes and cars for over 30 years - always with good results, but since I cannot get the correct grade for my Boxster S, I have gone over to Shell Helix Ultra 5W40 oil. If its good enough for Ferrari (as they point out on the packaging) its good enough for my lowly M96 engine..... As a point of interest, the first time I used the Shell oil (after it had been run exclusivly on Mobil 1 during the dealer warranty servicing) the oil darkened considerably after 3,000 miles of use. I changed the oil & filter again and now it hardly changes colour at all after the same 3,000-4,000 miles of service. Perhaps the Mobil 1 doesn't have the same amount cleaning agents that the Shell oil has....

M1 Euro brand (0-40) is a fine oil for your car. For that matter, any full syn Euro version would be fine.

Humm, I was thinking of trying 10w40 to see if it made the car a little quieter on cold starts. Also 0w40 seems outside of m ost of the advice I've read. 5w40 or 10w40 seem to be the two options. What do you think?

M1-Euro was factory fill for many years in the Box and 911.

Factory fill wasn't 0w40, though was it? Also, some argue that Mobil 1 ain't what it used to be. No idea whether this is true.

Well I have stayed with M-1 but I have the Castrol on the shelf in the garage. I just have not yet convinced myself to change it over. I actually do something many would think is odd. I use 5 quarts of the M-1 10W40 High Mileage and 4 quarts of M-1 Racing 4T 10W40 motorcycle oil. You see todays modern car oils in the US have been reformulated to SL/SM ratings for emissions and fuel economy. So much good additive stuff that is actually needed and good for the engine has been taken out. The motorcycle oil I use is still rated as SG which has many of the additives we need.

At this stage, I am totally flumoxed. Finding it very hard to choose an oil brand or grade. Bit of a nightmare! Need to get something ordered today and can't decide between 5w40 and 10w40. Car is a 97 with 85,000 on the clock.

Went for Fuchs Titan 5w40. Wasn't cheap, but is on the Porsche approved list and is fully synth SL. Oh well.

Pothole: another 5w40 rated synthetic you may want to research if you haven't already looked at it, is petrocan duron 5w40 synthetic. when i was researching the specs all the data sheets were out of the UK , therefore i assume petrocan is marketing it over there. i am running it 3 vehicles, a 99 passat 1.8T, a 99 beetle tdi, and the 06 boxster, UOA from the first looked okay, i will drop the boxster in the fall just before i park it and do a UOA on it at that time