Oil?

[gazzy]

I would appreciate any thoughts on the subject,my local Halfords have their own brand fully synthetic on offer,5w 30s.At £20 FOR 5 litres it seems a bargain,is it up to the job? or am I just being a tight northern git.

 

[Steve Brookes]

5W30 is no good for your car. The 30 means that it is too thin when up to operating temperature and won't offer enough protection. The second set of digits refers to the high temperature viscosity. The first digit plus letter is the cold start viscosity.You need it to be at least 5W40 for normal use. The choice of which 'W' to go for is a subject that often leads to a lively debate.

 

[iangray100]

I wouldn't put it in as its far too thin for a 964 engine as Steve says.
You will have very low oil pressure when the engine heats up if you did use it ...and that will kill the main bearing etc etc .
Mobil 1 Motorsport is what I use ..not cheap ! but neither is running a Porsche ....

 

[mcgc0]

As a fully-synth wouldn't Mobile 1 Motorsport contain a higher detergent value than semi-synth?

Apart from the benefits of this, I had this understanding that for high mileage engines using a high detergent oil will 'clean out' some of the build up of carbon deposits etc. The -ve of this being that any micro-meter play (or tolerance) between moving parts previously 'cushioned' or filled with the build up of carbon deposits, is 're-revealed' (if you know what I mean). The result being a slightly noisier engine and more free movement between those worn parts.

New/rebuilt/low-mileage engines then a no-brainer. Years ago I used to rebuild engines for all sorts and believe it or not we could run a rebuilt (petrol) engine on diesel oil, and often did. So long as you started with this and carried on using then fine. The benefit was a very high detergent oil preventing the build-up of carbon and oxidants. Mind you, if you switched to a mineral oil later you couldn't go back.

Maybe, and hopefully, oil technology has moved on considerably. I might call up Castrol or somebody and see if there is a fully synth oil recommended for high mileage engines (or of very low detergent content).

Marcus

 

[colin129]

I always understood that Mobil 1 was too thin for our engines & has a tedency to find all the places to leak from.

Where I get my car serviced I think they use Castrol GTX Magnatec

 

[mcgc0]

Mobil 1 is indeed generally the thin oil (i.e. 0W-20/40) fully synthetic with good cold starting - it's thin!

Mobile 1 Motorsport though is fully-synth again but actually 15W-50, which is unusual, as nearly all/most fully-synth oils are around the 0W or 5W.

Mineral oils (or cheap engine oil!) = more frequent oil changes (sludge and anti-oxidant build up).

The question for me is more around finding the optimum performance balance for engine of 100k miles or more. If I find more I'll post..

Marcus

 

[Melv]

Mobil 1 Motorsport

Say no more..............

 

[gazzy]

My original question was about 5 30s weight,I feel you are correct in that it probably isn't up to higher temperatures but now it's wether or not fully synthetic is the way to go.I have always felt it was a waste of money on my bikes,some of which I ran with fairly high compression and nitrous without problems,however I'm relatively new to Porsche's and just followed the trend towards fully synthetic,a couple of the comments have made me now think otherwise.Basically it's a 100,000 miler,is fully synthetic a waste of money and of questionable use ?

 

[mcgc0]

Got through to some oil geek at Mobil and he then sent me the reply below. There are fully synth oils of the same multigrade SAE but of different quality/cost. I guess Mel is spot on with his use and works well for him.

You go to somewhere like Opie oils and then look up oils that meet the Porsche A40 spec and you'll get 15 results (of which only two are semi-synth). The low cold point is 0w or 5w. The difference then is down to additives for different uses and qualities.

Me, I'm going to try the Mobil one below. And to answer your original question, maybe you are trying to be a a financially prudent person of the North []

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According to my database 15W-50 isn't the right grade for your car, you should use Mobil 1 Peak Life 5W-50 instead. It's an oil designed for aged engines.

http://www.mobil.com/UK-English/Lubes/PDS/GLXXENPVLMOMobil_1_Peak_Life_5W-50.aspx

To answer your question, yes, if low detergency oils have been used, Mobil 1 Peak Life 5W-50 can remove a lot of dirt at the beginning, you may want to keep an eye on the filters and replace them if necessary.

 

[Dekker]

ORIGINAL: Melv

Mobil 1 Motorsport

Say no more..............

Mobile 1 Motorsport

Hi Melv, I wonder if you've changed your oil type since the engine failure last month?

David.

 

[h_____]

Yeah Melv, I mean that engine is always being rebuilt and only gets driven to the shops gently on Sundays! [][]