Mobil 1 - am i doing the best for my new baby?

[vinceg]

I am due a 12k service for my new '97 993 C2S "" 47k miles and booked her in today for next month at a major independent. I am a long term fan of Mobil 1 in my cars so post review of the PCGB forum thread on this subject elected to go for 0-40w Mobil 1 which seems approved etc. I bought said oil ( 12ltr) last weekend so it's now ready and waiting.

Two questions:

1) Is Mobil 1 not an ideal oil for a 993. When I booked appointment today seemed this was being implied without being said "" what views. I want the best for my baby.

2) On viscosity I went for 0-40 but was advised that 10-40 would be a better bet as 0-40 is so thin it may well show gasket leaks not previously seen. Is this so, is 10-40 the right grade. I couldn't even see this on the "˜approved' oils listing of the forum. There is a Mobil 1 5-40 lsited but non a 10-40 Mobile 1 althoughthere is a Mobil super 10-40 which I have not seen in the usual outlets. I have no leaks now and keen to keep it that way. Am I good with 0-40, being paranoid, or should I put in something else?

Vg

 

[burrow01]

Hi,

Where are you taking your car for the service? Lots of independents do not seem to like Mobil 1 - I had a big discussion last time I took my car for a service, as they thought Mobil 1 was a waste of money in an older car and wanted to put in a semi-synthetic oil - I insisted on Mobil 1, as the engines were designed for it, and I have used it since the late 80's.

With regard to viscocity, do you have any idea what is in at the moment? I have always used the 0W-40, and have not had any oil leak problems.

10W sounds a bit thick for the UK, if you start to get oil leaks with the 0W, you can always try thicker oil the next time?

Pete

 

[pae]

Different, but even older, car.

When I first had my 924S (1988 model) serviced by Parr Garage they put Mobil1 0W-40 in it, and they were happy that it was suitable for the engine. And it was, never leaked a drop.

Personally I think it's the best you can get, so use it if that's what you'd like to put in it. I always used Mobil1 after that first time - I've no idea what was in before I had it serviced.

As Pete says, you can always go to slightly thicker if you find it does leak a bit. Bet it won't though.

Phil

 

[John Maddox]

I agree with Pete I wouldn't use a 10W-40 in my 993 all year round.

I am pretty sure most main stream fully synthetic 5W-40 oils are on the "Porsche Approved List" and this grade used to be the Porsche recomendation for our cars.

I think Mobil 1 went 0W-40 to gain extended service classification of VW/Audi and the like.

I have heard that 0W-40 can seek out weak gaskets and leak but not seen any real evidence to back this up.

I am not an expert in this, just an enthusiastic 993 owner who does his own servicing etc so you will have to decide !!

Regards

John

 

[968er]

If a fully synthetic engine oil has always been used in your engine then you are unlikley to see any leaks, however, it is when you put in a fully synth oil in an older engine that has been using semi-synth that the c;eaning agents do too thourgh a job and clean out crude arouind seals that will result in a leak that you had otherwise not seen.

I have had similar conversations around Mobil 1 with tchnical people and the general opinion is that it is a very successful marketing ploy as there are better oils available on the market, but it has to be remembered that these discussions were on track/racing use. Thre is also the arguement that it is not actually a fully synthetic oil. It is something to do with esters etc. One of the Castrol oils always comes highly recommended and cannot remember its name at the moment.

Bottom line, you want an oil that will protect the engine and not breakdown. If Mobil 1 does that, then there is no reason to change.

 

[38F3E1]

The most common consensus on viscosity seems to be 5W-40 but as you will discover everyone has an opinion. As you have already bought the oil then stick the 0W-40 in it. It will be fine. If it leaks just go 5W-40 next time or 10W-40 if your indi can convince you why.

As long as it's a fully synthetic (and preferably on the approved list) you will treating the car as it should be. I happen to always use Motul in my car but that's just my personal preference (Motul 300V 10W-40 at the moment for summer use).

Ian

 

[Sundeep]

Mobil 1 works but it can leak....

I'm using Silkolene Pro S 5W-40, pricy but is supposed to be the best around !

 

[Rotorhead]

Mobil 1 have done a great marketing job, but I'm sure there are other equally efficient engine oils.

I don't like using 0W oils in my older cars and I don't think it gets cold enough in the UK to necessitate them.

My OPC uses a range of Castrol products and we normally discuss what is most suitable depending on the car, its age/mileage, usage and service.

 

[vinceg]

Thanks for all the feedback. Will probably go the Silkolene root as that seems - from feedback here and pistonheads - to be somewhat the recoignised as 'best' athough pricy. In my view cheap engineering in the scheme of things so I'll go that way.

Anyone what to buy the 12l of Mobil 1 0-40W I now have and not required. Open to offers.

One aspect that does somewhat confuse me is I understood that a 0-40 and 10-40 had pretty much same thickness - by defintion of the rating - when hot so that would not explain peoples perceptions of greater leak issues on a 0-40. Am I wrong on this?

vg

 

[38F3E1]

No you are absolutely spot on but ...

When hot they will be the exact same thickness. When cold the 0W will be thinner than the 10W but both will still be much thicker than when it is hot so you might think "why the difference in leakyness and why doesn't it leak when hot then?".

The reason is that when the engine is hot all the metal parts have expanded and everything is nice and tight and no gaps for leaks.

When cold an aircooled Porsche engine is rather 'loose' in engineering terms and because the 0W is thinner than the 10W at these temperatures it tends to leak more out of the gaps that have appeared.

Ian.

 

[oilman]

I would certainly stick with the 0w-40 or 5w-40 which is the viscosity that Porsche recommend.

Mobil1 is a good oil but then there are also other good ones, better in fact if the car is tracked.

You pay your money and take your choice, choose according to your type of use and budget but always buy the best you can for your Porsche as it's not a nissan micra!

Cheers
Simon