Vwb het gebruik van 10W60 maakt het wel een verschil of het gaat om een 996 of een luchtgekoelde P:
Ik herinner me een goed stukje hierover van een ander forum, en na even zoeken:
The last porsche oil recommendation TSB for the 993 was in 2003, and widest weight spread was 45 ex: 5W-50 (which they recommend)
you can find the TSB I posted on pcarworkshop with complementary docs.
10W-60 was developed in 2004 by castrol and BMW, for the BMW M engines pre year 2000.
premature wear in all M series engines of camshafts valve tappets crank journals were a result of low levels of zddp in the newer oils.
Tolerances in the 993 engine were more than the post-2000 engines, thus needed elevated levels of zinc etc, as anti-friction agents.
And to lubricate best an engine when hot, you need higher viscosity (thus pressure)
End product was so breakthrough, they produced the same viscosity range for new engines API SM-SP. Without high zddp levels,
Before was called RS-Formula, today the name is Castrol Edge Sport 10W-60. (which is the Castrol edge 10w-60 with low zddp)
So Castrol Edge Sport 10W-60 API SM-SP for new cars
Castrol Edge 10W-60 API SJ for pre-2000 cars
BMW can develop an oil for a fleet of M series they had to stand to.
En wat me vooral is bijgebleven

:
There is absolutely NO argument for using a 60 weight oil in a road-going 993 engine in the UK climate.
None whatsoever.
Why?
1) Put simply, every engine is designed to work most efficiently at running temperature with a certain oil 'weight', and then a multigrade oil is specified to allow for ambient temperature variation on engine start-up.
As you have stated, the Drivers Manual details these ranges. 10W60 ain't one of them.
2) the clue is in the name of the oil - Motorsport. If you race an engine, the parameters stated above now shift to a higher 'weight' of oil, which will exhibit the SAME original-engine design target viscosity at the HIGHER temperatures that are seen during prolonged high rev ranges - i.e. racing.
I'm sorry, but whoever says a 60 weight oil is correct for a road-going 993 has no idea what they are talking about, and all of their other 'advice' should be treated with extreme caution.
Once you put the correct 40 weight into your engine, you will notice a large increase in power, as the engine no longer has to move 11.5 litres of treacle around.Porsche did not produce too many 993's to co-produce a specific oil.
(voor de duidelijkheid: Dit zijn twee verschillende auteurs in een draadje op 911uk forum

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