Engine Oil

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All engine oils are the same – right? Absolutely not! Here’s some other myths worth dispelling if you want to make your classic’s power unit last the course

CLASSIC OILS CAN LOOK A BIT PRICEY

FACT We can’t disagree with that but, as in all walks of like, you get what you pay for and the specific nature of a classic oil costs more than a normal mainstream lubricant, due to weight of numbers as much as anything else. But you need to put this into perspective; if you have an expensive classic (as most are) or have just shelled out thousands on a restoration or engine overhaul, the extra perceived cost of a classic oil is minimal compared to what it protects. In short, a classic oil is an investment as much as anything else.

I DON’T NEED A CLASSIC OIL

FICTION Well, sort of. So long as you use the right oil for your car as recommended when new – and these are still widely available – then you should be okay. However, the benefit of a modern classic engine oil is that they broadly provide the best of both worlds, chiefly current standards of quality but twinned with traditionally refined formulations for the eras these oils were intended for

IT’S THE NAME THAT COUNTS

FICTION No! Yes, it’s true that the you can sleep easier with the better known and respected brands but this doesn’t imply that lesser names (perhaps better known by the trade rather than the retail sector) don’t supply equally good products.

A MODERN OIL MUST DO THE JOB BETTER

FICTION This is a pretty logical thought yet dangerous thinking at the same time because while you’d expect a modern super-duper synthetic lubricant to provide the best protection you can buy, the reality is that they are totally unsuitable for old engines because they are designed for today’s power units which feature tighter working tolerances, higher pressures and faster speeds. Also, a modern lube has to take into account ancillaries such as dual particle filters, catalysts and more. It sounds daft but, in fact, a modern oil will ultimately do your old Jag XK more harm than good! BTN Turbos claims a staggering 91 per cent of warranty claims are down to motorists – and mechanics – using the incorrect oil for that particular engine!

THERE’S SO MANY AROUND

FACT Nobody knows the exact numbers of lubes on sale, but if you include small independent suppliers, there must be well over 100 different brands and brews on the market, all varying in price, grade and quality!

ANY OIL WILL DO

FICTION While they look pretty much the same and perform the sale role, modern engine oils aren’t and that’s due to the specific needs of today’s car makers. Agreed, back in the 1960s and 70s, a typical engine oil could serve most engines well but it’s not the case any more, especially so for power units designed since the 1990s.

I HEAR THAT A MODERN DIESEL OIL IS A PRETTY GOOD SUBSTITUTE FOR CLASSIC

FACT And fiction all at the same time. This is all down to modern classics of the 1990s and the zinc make up that’s found in an oil. The very latest oils major on emission control and are blended as such. For example, to prolong the life of a catalytic converter, today’s oils have severely cut down on the zinc (ZDDP) contingent. This is fine except that zinc is a superb anti-wear agent and so its reduction can lead to excessive piston ring and camshaft wear – Imprezas can particularly suffer here. A diesel oil posseses more detergents than a petrol one and this can counteract the potential problem but, it’s really playing Russian roulette and better off with a classic oil.

THE SPECS FOUND ON THE OIL PACKS IS JUST MUMBO-JUMBO

FICTION They are the most vital indicators on an oil pack – far more important than the brand or price in fact. Check out any good quality pack of oil and you’ll probably see a lot of numbers and letters. To the uninitiated it looks confusing, yet in fact this coding is pretty easy to crack. ‘ACEA’ (a respected European governing body) ranks oil quality from A1/B1 upwards (A standing for petrol, B for diesel). A more familiar standard is the old American API body which uses plain lettering. S stands for ‘spark’ meaning petrol (C for compression ‘diesel). SN is the most current standard but you can still find SF ratings which was introduced 40 years ago.

Apart from these markings, look out also for listed approvals from leading carmakers which is taking more prominence as they increasingly demand a special oil for their specific engines; it’s reckoned the German makers (BMW, VW, Audi, Mercedes and Porsche) remain the fussiest around and as a result their ‘rubber stamps’ are highly valued on an oil’s pack. Similarly, you can find Ford-branded Castrol oils made especially for its engines. Failing this, check out the websites of the oil marketeers such as Castrol, Comma etc; Halfords stores have an easy point-of-sale store guide along with helpful coloured oil packs, too.

LASTS FOREVER SO BUY IF CHEAP

FICTION Today’s oils have a ‘best before’ date on their packs because modern synthetics, in particular, can separate when left in long term storage, say more than four years. This is why you sometimes see oils being sold at bargain prices before they ‘go off’; Comma suggests a five year life after production date, as an example. For this reason, be wary of very old lubricants being sold at autojumbles which may now be non serviceable. This also includes greases where a ‘scum’ can rise to the top and needs to be skimmed off before using.

SYNTHETICS OFFER BEST PROTECTION

FACT It depends on the engine and the more modern it is, then the tendency is to go for a man-made lubricant. Synthetic oils first came to prominence in the early 1970s but were decidedly specialist and didn’t become a high street option until a decade later with the introduction of Performance Oils. There’s two types, semi and fully synthetic and essentially these man made oils are superior because they can be brewed and blended from scratch plus boast a wider working range and also are longer lasting in service. Sounds great, but they may not suit your oldie. For a start, unless you opt for a classic type, they will be lighter and thinner than desired, and on old engines with their wider working tolerance this will lead to low oil pressure and probably excessive consumption. Also, by design, synthetics are cleaner living and have a dredging effect, so disturbing old latent residue in the engine, which is better left alone. If you insist on going the synthetic route (and for many owners, it’s a waste of time and money) then you will at least have to flush the engine out first and possibly drop the sump to clean out any muck – you’ll be surprised the amount there!

CLASSIC OILS ARE SIMPLY OLD TECH MINERAL STUFF IN A FANCY WRAPPING

FICTION A misconception because such is the wide variety around, there’s a type for all classic engines of all eras. Mineral, semi-synthetic, fully synthetic and even dedicated vintage, veteran and motorsport type are offered, the latter where Millers even produces a special high tech 20W/50 with low friction properties like a synthetic. The trick is to pick the right one for your classic so speak to a marque or engine specialist first rather than your average workshop mechanic as they are just as much in the dark about what’s the right and wrong oil as we are! According to Comma, a 10W/40 grade oil remains the most popular pick, accounting for 42 per cent of sales, and yet only12 per cent of vehicles now require this oil grade; this means almost a third of us are using the wrong lubricant! There’s also seven types of 5W/30, too. So even when you think you’ve got it right you possibly haven’t…

THE THICKER THE OIL THE BETTER

FICTION Motorists recognise an oil by its name and the numbers (technically known as viscosity, to the layman it means thickness) it displays. We’ve all heard of 10W/30 and 20W/50 (‘W’ means Winter) and in the majority of cases this is what your classic will cheerfully run on. However, the thickness doesn’t automatically mean it is a better protectant and using a stronger grade in an engine not designed for it can cause problems as it struggles to pass through oil ways with working tolerances not designed for a thick lubricant, especially when cold. The exception is when the engine is worn and burning oil; here a slightly thicker lube – say the next grade up – can help reduce the problem as well as improve flagging oil pressures. It’s here where a classic oil can particularly help as they are invariably fuller-bodied and you can opt for a 20W/60 or 10W/60 oil if desired.

CHEAP OILS DO THIS

FICTION True, you can easily find very low-priced lubricants – typically 20W/50 – around but these invariably also come with the lowest specifications they can get away with and will not provide the level of protection you need, quite unlike a quality classic lubricant. In fact, many cheaper oils commonly display no specs at all – make of that what you will!

ALL AN OIL DOES IS TO SIMPLY STOP SLIDING SURFACES RUBBING TOGETHER

FICTION Granted, a lubricant’s main job is to do that, but it also cleans away harmful by products such as acids, coke, tarnish deposits and so on which are part and parcel of the combustion cycle. Also it must do so for thousands of miles under all extremes of driving conditions, from cold start school runs to fast drives up the M1.

How long will an engine last without oil in it? In 1972, additive company Molyslip took two Ford Mk2 Cortinas to the Crystal Palace racing circuit and allowed journalists to drive them – both were bone dry of oil but one had been treated to Moly from new. Apparently, the Molysliped Cortina drove for some 90 miles and proceedings were only halted due to boredom. When the rattly yet sound engine was stripped down it was still in serviceable condition, unlike the unprotected Kent engine which, to its eternal credit, lasted for no more than 10 laps…

OIL’S WELL

• Change the oil regularly – despite the cost of quality lubricants they are a cheap insurance
• Oil accounts for up to a third of the engine’s cooling capabilities, which is why it’s important to keep the oil clean and topped up
• Known names and favourite brands are part and parcel of purchasing choice but it’s the specs on the oil pack that say the most; a cheaper, lesser known brand that’s boasting all the right labels is as good
• A regular engine flush is a good idea to remove any harmful sediments which are building up, as is dropping the sump pan to clean out the container and the oil strainer
• It’s not just engines that can be given the classic touch. Transmissions and greases are also available and the same reasoning and warnings apply. There’s also running in oil which is a deliberate low quality lube for controlled bedding in. Laying your car up this winter? Then you can opt for a storage oil which gives off a fine mist to coat the inners during lay up