Your Oil Questions answered

I would just like to take this opportunity to than Simon for the great advice, and great service that he provides.

I ordered two 5L bottles of Silkolene Pro S 5w40 oil, and it arrived the next day, as advertised.

I am also very pleased with the price that I paid. I won't go into exact details, but 10 litres of very good oil was delivered to my door for a good bit less money than you can get  8 litres of Castrol RS or Mobil 1 from Halfrauds.

I for one will be making future orders

Cheers,

Ian.

Fransisco,

BMW recommend "all year round" the following grades:

0w-30

0w-40

5w-40

So yes what you are using looks fine, I would question the change in the summer though as these are "all year round" recommendations.

Hope this helps.

Simon

Do you reckon I should the Castrol RS 0W40 all year around on my M roadster? Is it any good?

By the way why is BMW recommending (it says on the bottle) that Castrol TWS is THE oil for M5, M3, and Z8?

cheers

Francisco

Shoestring 7.

I'll presume that you have not put anything in it since the rebuild.

Do not, I repeat do not use semi or fully synthetic for 1000 miles.

You need the lowest grade mineral oil that you can find, a 10w-40, 15w-40 or even 20w-50 with an API of around SF.

You must do this as it is the only way to bed the engine in properly.

Cheers

Simon

I just posted this in the M Power Forum and thought it may be useful here as well!

The question was my views on Redline?

Redline.

It may be best that all Redline fans close their ears or look away at this point, you may not like what you read!

Some basics first.

A good oil must be quite low in viscosity even in the cold, so that it gets around the engine in a fraction of a second on start-up. On the other hand, it must also protect engine components (piston rings for example) at temperatures up to 300 deg C without evaporating or carbonising, and maintain oil pressure.

Unmodified thin oils simply can't manage this balancing act. The answer is to use a mixture of thin oil and temperature sensitive polymer, so as the thin oil gets even thinner with increasing temperatures as the engine warms up, the polymer expands and fights back, keeping the viscosity at a reasonable level to hold oil pressure and film thickness on the bearings.

All oils have a viscosity index which is the number indicating that rate of change in viscosity of an oil within a given temperature range. Higher numbers indicate a low change, lower numbers indicate a relatively large change. The higher the number the better. This is one major property of an oil that keeps your bearings happy. These numbers can only be compared within a viscosity range (10w-40 vs 10w-40) but here it the important thing...............

They do not give an indication of how well the oil resists thermal breakdown! (The oil film tearing or shearing)

This is all down to a very important additive called a Viscosity Index improver and it is critical that this is shear stable.

VI improvers like all other things in life vary in quality and this is down to cost and availability.

In other words, an oil can look great on paper and make impressive claims but, unless all the components are of high quality it will fail to perform under the most arduous conditions.

I asked John Rowland the Silkolene/Fuchs Chief R&D Chemist for 40 years to give me his opinion on U.S. oils (including Redline) for

another car club and below was his reply:

Quote:

Simon,

Redline and all U.S. oils. The main problem with these is that all American Oils have "low grade" Viscosity improvers in them. Good ones are just not available in the states due to the fact that they are just not required for the majority of American engines.

The consequence of this is, although the oils look good on paper with high VI indexes etc they have low grade inprovers so they have a tendency to "shear down" causing a lack of back pressure.

For example, the oil you are using may be a 10w-40 but could be operating when hot a 20!

JR

Unquote:

I was intrigued by Johns answer and wanted to know how he knew it was the case in the U.S. that good quality VI improvers were not available. His reply was as follows:

Quote:

We have found it is impossible to source shear stable VI improvers

in the U.S.A. even for ready money!

Unquote:

Bear in mind here that Fuchs/Silkolene is the largest independent Lube Oil Manufacturer in the World and has facilities in the U.S. 

So, there you have it, another expensive oil that is not all it's cracked up to be!

Mis-information abounds in the oil world and looking behind the marketing hype and claims is impossible unless of course you are a chemist and able to look deep into the oils make-up which neither you nor I can do!

This may be the time to tell you all something that you will probably not be aware of.

FUCHS, the parent company of SILKOLENE supplies 30% of all BMW's oils for factory fill. More than 5,000,000 litres per annum so it is probably fair to say that BMW trust them and.................your car has a 30% chance of arriving in this country with FUCHS oil in it!

Sorry If I've offended anyone but I promised to be frank and honest.

Cheers

Simon

Simon,

My '89 M3 has just had its engine re-built (+.030 re-bore, new pistons etc etc).

Would you recommend a different oil for the initial running-in period, or should I fill with a fully synthetic 5W-40 from the get-go?

Cheers,

SS7

Eamo,

Would recommend you use "all year round" a 5w-40 fully synthetic meeting CCMC G5

Or for -20 to 20 degrees you can use a G5 10w-40 semi-syn (the cheaper option)

The fully will give better protection for reasons stated earlier on this thread.

Cheers

Simon

Check your PM's please.

Sleeper.

The recommended specs are as follows:

BMW LL98 (Now replaced by LL01)

ACEA A2/A3

The choices you have are as follows:

0w-40 Fully Syn (LL01/98)

5w-40 Fully Syn (ACEA A2/A3)

10w-40 Semi Syn (ACEA A2/A3)

I have a fairly long list but you need to consider price against how often you change the oil to detemine the best solution.

Recommendation (based on meeting the above specs)

Castrol RS Power 0w-40 Fully Syn (LL01/98)

Mobil 1 0w-40 Fully Syn (LL01/98)

Fuchs Titan Supersyn SL 5w-40 Fully Syn (ACEA A3)

Silkolene PRO S 5w-40 Ester Fully Syn (ACEA A3)

Total Quartz 9000 5w-40 Fully Syn (ACEA A3)

Silkolene or Fuchs XTR 10w-40 Semi-syn (ACEA A3)

Castrol Performance 10w-40 Semi-syn (ACEA A3)

All the above are BMW Approved but personally I would use a 5w-40 Fully syn as it will give better protection than the Semi-syns but does not cost as much as the 0w's.

If you would like some prices, you'll need to email me.

Hope this helps,

Cheers

Simon

Recommendations

If you would like recommendations, to speed up my response it would be most helpful if you could provide the following information:

Make

Model

Year

Engine size

Engine type (petrol/diesel)

Any Mods

Handbook recommendations are also helpful in the case of some models but not essential.

Thanks for your cooperation

Simon Barnard