Classic Oils

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When it comes to protecting your cherished classic, you must demand ‘pour quality’ in the oils that lubricate it. Here’s how to ensure you get it…

Pour quality, not poor quality, that must be your mantra when choosing the best oils for your coveted classic. It’s not simply a question of love – with the value of your prized vehicle ever appreciating you’d be mad not to protect what is, quite probably its single most expensive component to replace – the engine!

It used to be so simple back in the good old days. If you needed a good engine oil you just popped down to your local motorists’ shop and bought mainly Castrol GTX or Duckhams Q. But now, with more than 100 different brands and blends of engine oil on sale, it’s oh so easy to use the wrong type and do more harm than good.

In fact, so specialised are some of today’s advanced lubricants that an increasing number even have their own part number at main dealers, meaning that if you use the wrong oil (and seasoned mechanics can be just as guilty of this) you’ll probably invalidate the VM’s warranty!

We’re still doing it. According to Comma, a traditional 10W/40 grade oil remains the most popular pick, accounting for 42 per cent of sales, despite the fact that only 12 per cent of engines now require this oil grade. Also, there are seven types of 5W/30, so even when you think you’ve got it right, you probably haven’t!

In contrast, the simplicity of choosing a classic alternative has seen their sales soar. Porsche, for instance, introduced its own line of classic engine oils (20W/50 and 10W/60) in 2015 and has more than 120,000 litres of this lovely lube, because it’s made for classic Porsche engines, which up to the 1970s required a special singlegrade oil. Classic Motoroil is suited for the higher-temperature air-cooled units plus, and, unlike modern synthetic types, it won’t dredge up latent nasties or damage oil seals and so lead to leaks. To complement its Motoroil, Porsche has also reintroduced its original red coloured oil filters.

Why go classic?

On the face of it, you’d think that the newer, more advanced the lube, then the better it would be. However this is not so, because their modern mixtures take into account emissions, catalytic converters and so on, so they won’t protect your classic’s engine any better – in fact quite the opposite.

Take this as an example: The very latest oils major on emission control and are blended to prolong the life of a catalytic converter. As a result, they contain a severely reduced zinc (ZDDP) content, which is fine – except that zinc is a great anti-wear agent, so any reduction can lead to excessive piston ring and camshaft wear on older yet relatively modern engines – Sierra Cosworth and Imprezas spring to mind.

Conversely, a plain budget brew – a typically 20W/50 oil – may well have been the ideal when MGBs were in the showrooms 50 years ago, but its overall specs and quality are now too inferior for what’s demanded by modern motoring.

A classic oil strikes the perfect balance by providing current standards of quality, twinned with traditionally refined formulations for the eras these lubricant were intended for.

Making the grade The traditional ‘multi-grade’ that’s now the default pick came about largely thanks to the original Mini, because its transversely mounted engine used the same oil to also lubricate the transmission, making straight ‘mono grade’ oils unsuitable. Before this, straight oil grades were the norm and had to be changed to suit the seasons, with a lighter ‘20’ or ‘30’ grade forwinter and a thicker lube for the summer when the going gets hot.

Again, referring back to our earlier comments concerning oils right for their engine designs and eras, classics dating back to the 1940s may be better off with a ‘monograde’ oil and some air-cooled VW enthusiasts will use nothing else still. Also, certain engines shouldn’t use an oil which contains detergents; speak to your specialist or car club for advice on this.

Motorists recognise oil by its name and numbers (technically known as viscosity but to the layman thickness) it carries. 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 run on.

The first major change to lubricants occurred 30 years ago, with the advent of Performance Oils (semi or fully synthetic) to counter what was known as ‘Black Death’ sludging. During this decade, oils became much thinner and more specialist. A phenomenon known as ‘valve stick’ plagued certain engines in the 1990s and this ultimately led to today’s ultra-thin oils.

However, thickness doesn’t automatically equate to better protection and using a thicker grade in an engine not designed for it will cause problems, as it struggles to pass through oil ways and working tolerances (such as bearings) not designed for it, especially when cold.

The main exception is when the engine is worn and burning oil. Here, a slightly thicker grade of oil – say the next one up – can help reduce the problem, as well as improve flagging oil pressure issues. It’s here that classic oils can help, as they are invariably much fullerbodied and you can also opt for a 20W/60 or 10W/60 oil if desired.

If this doesn’t work, then consider a dedicated oil to counter this, such as No Smoke Oil (www. nosmokeoil.com) that claims to permanently reduce the James Bond-like smokescreen. It comes in three grades: 10W/40, 20W/60 and even a modern 5W/30 to cater for most power units. As we run a superb but smoking Alvis TA, we’ll be trying some and will be reporting back – with a typical sumpful for an MGB costing just under £60, it’s got to be a cheaper option than an engine rebuild.

As the popularity of classic oils has soared, so has the range of brews now available, offering various viscosities, specifications, synthetic types and even special motorsport brews. While not half as complicated as mainstream choices, you do now need to speak to a classic oil specialist (Penrite, Millers Oils, Morris Lubricants, Valvoline, Castrol, and recently Shell who relaunched its classic X100) to see what’s right for your vehicle and application.

Racing enthusiasts will know the name Agip who lubricants have been used by Ferrari for decades. Another lube line worth looking at is Eri’s i-Sint lubricants where a select cluster of classic brews are offered including ‘Professional’ alternatives, aimed at mechanics and workshop use.

Both ranges are available from Moto World UK, which is part of the Superformance Group and sole UK importer of these quality lubricants.

Racing names are fine but using pure racing oils on the road may do more harm than good. On the face of it, their higher specs and standards sound tempting, particularly if your engine is highly tuned, but these lubes are usually tailored for continual high rev, high load use, and so will be unsuitable for normal pottering around – Castrol’s classic R40 racing oil, that’s vegetable-based, springs to mind. Also, competition oils may contain abnormal zinc levels for added protection but the flip side is higher emissions and a cat-equipped classic could well fail the MoT on this point, as well as ultimately killing the cat.

Sinful synthetics

There are two types, semi and fullysynthetic and both are essentially man-made oils. As a result, they are superior because they can be brewed and blended from scratch and to exact specifications, plus boast a longer service life. That said, they may not suit your oldie. For a start, unless you opt for a classic type, they will be lighter and thinner, and on old engines – even good condition ones – with their wider working tolerances, this will lead to lower oil pressure and probably excessive consumption. Worse still, synthetic oils have a ‘dredging’ effect, so disturbing decade’s old latent residue in the engine. This is better left alone rather than having it now circulating the engine’s internals and perhaps clogging up vital oil ways. If you insist on switching over – which, for many owners, will be a waste of time and money – then you will at least have to flush the engine out beforehand and possibly drop the sump to clean out stubborn muck – you’ll be surprised the amount found there!

The price of protection We’re staunch fans of classic oils but have to admit that they come at a price. Top quality lubricants – both contemporary or classic types – are always premium priced and a typical sump load for a Jaguar Mk2 will cost you a handsome £80 or so. And, as classics are used infrequently, it’s advised to change the oil annually, especially before a winter lay-up, so that any corrosive by-products of combustion are expelled, adding up to a sizeable outlay.

In the end, it depends how much you value your classic. A proper rebuild on an XK engine costs around £5000 so, in the grand scheme of things, splashing out on an appropriate oil is cheap insurance really.