What oil to use?

Guest · Jun 30, 2005

Took your advice people. Re-mortaged the house, sold my soul to the devil and put my daughter in to the slave trade. At least I will have sexy oil delivered tomorrow. Not to forget impending divorce over magnetic synt. or not - "Merc dealishership uses it in their sports cars so must be best and I'm spending half the money you are - daft cow - or words to that effect.) .

At the end of the day I want my car right and get 0-60 in the correct time. Not drive my old mans car and get to 60 in years. Fuel allowance will be nice!

Oilman - for that price - does it work on wrinkles!

oilman · Jun 30, 2005

Never tried it but it does most other things. Sings and dances too!

Seriously, it's insurance and cheap considering what the car is worth and the bills when things go wrong!

Cheers

berg944 · Jun 30, 2005

Can anybody list the real synthetics?

oilman · Jun 30, 2005

Now, that's difficult as most (but not all) manufacturers will not divulge the basestocks used.

As a rule of thumb.

All 0w oils are synthetic (pao or pao/ester)

5w oils are a mixed bag as this rating can be achieved with "hydrocracked" petroleum basestocks and a nominal percentage of pao.

10w and 15w are almost all mineral oils or modified ones.

There are some noteable exceptions to the rul though.

Mobil1 (pao)
Silkolene PRO (pao/ester)
Motul 300V (pao/ester)
Motul 8100 (pao and or pao/ester 0w)
Fuchs Titan Supersyn (pao)
Redline (pao/ester)

TBH it's a minefield but pao/ester are the best quality oils because of the "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.

Hope this helps,

Cheers
Simon

dlknight · Jun 30, 2005

Hey all,

Im currently using Castrol GTX Magnatec 15w40 in my 944S - these are the details from Castrol's website:

"Castrol GTX Magnatec for Conventional Engines has been synthetically engineered to provide enhanced protection for this specific use. Containing a unique synthetic ester that clings to the engine surfaces like a magnet, Castrol GTX Magnatec protects your engine from the moment you turn the key"

Now as I understand it this is a hybrid oil which is a blend of synthetic esthers and mineral based stock ?

Cheers

Dave K.

oilman · Jun 30, 2005

It is not a synthetic oil in the true sense of the word (group 4 and 5 basestocks), it's clever marketing, somewhat mimicking the real thing. It's almost 100% group 2 basestock (mineral oil) with a small percentage of ester to give the polarity claim. A real synthetic would be 80% pao / 20% ester and costs more as there is no petroleum basestock in it at all.

Cheers
Simon