997 Turbo oil?

[AMG Merc]

Apologies, I expect this has come up in the past...

I use the prescribed Mobil 1 fully synthetic 'New Life' 0W-40 oil. I'm wondering if the thinness makes the the sewing machine behind my head sound a bit too agricultural on cold startups. Has anyone tried say Mobil 'Motorsports formula' 15W-50?

[EvoSlayer]

I've been using the Mobil 15w50 Motorsport stuff in my modified 996 turbo for a few years now but it seems to be getting more difficult to get hold of so I now have a stash of the millers nano-drive 10w50 for the next change. FYI car has covered 41k and is generally laid up over Winter once they start chucking salt on the roads.

[Rockster]

AMG Merc said:

Apologies, I expect this has come up in the past...

I use the prescribed Mobil 1 fully synthetic 'New Life' 0W-40 oil. I'm wondering if the thinness makes the the sewing machine behind my head sound a bit too agricultural on cold startups. Has anyone tried say Mobil 'Motorsports formula' 15W-50?

The sewing machine behind your head is a mega monster IC reciprocating engine with 4 valves per cylinder, advanced valve timing and lift control, high pressure injectors and high powered coils coupled with a tuned exhaust system all working togehter to horsepower at a level that would require a NA engine 1.6 times its displacement to duplicate. (For example, while my 3.6l Turbo engine produces a bit over 400hp it took 6.0l from my GTO engine to make about the same hp.)

The noise is normal. Part of the noise comes from the VarioCam Plus and the low lift hardware along with the usual clatter of zero lash lifters pumping up and cam chains with a bit of play getting stretched as the tensioners gain oil pressure. All this should go away in a second or less. The engine still sounds a bit ragged but this in due to the rich running condition coupled with the low intake valve lift to reduce engine friction when cold and lower emissions. The rich condition supplies fuel that is burned in the converters to warm them up quicker so the engine controller can switch to closed loop operation sooner and then cut back on the fuel. This makes for a cleaner running engine which among other things contaminates its oil less which helps prolong engine life.

15w-50 is not an approved oil probably because it is too thick to flow properly at cold engine start. It probably doesn't have the suitable additive package and has other shortcomings too.

My 03 996 Turbo engine has 110K miles on it and runs 0w-40 oil. (My 02 Boxster engine has 270K miles on it and runs Mobil 1 0w-40 oil). And there is a USA 996 Turbo S that has covered over 350K miles and the owner runs Mobil 1 0w-40 oil. It can't be that bad...even for your 997 Turbo.

[RAWENG]

15W50 is too thick for hydraulic lifters to work efficiently. We had ioads of trouble running this viscosity in tuned K series engines in Caterhams and 5W40 is as thick as I would ever go . I would use the recommended viscosity 0W40 to avoid problems