Latest News:

autotechnician - serving the independent workshop - logo

Avoiding oils going rogue

There is so much going on with lubricants to trip up even experienced technicians, leading Rob Marshall to look at the latest situation.

With so much attention focussed on electrification, it is easy to forget that internal combustion engines are still very much in production. Indeed, ICE and drivetrain developments are continuing, despite them not attracting as many column inches. As engines and drivetrain are designed in close collaboration with lubricant providers, it is unsurprising that oils too have become far more sophisticated. This is not just to make life difficult for us. They are integral to the machinery that enable long life, optimum efficiency and minimal pollution.

Latest developments

Especially with more recent models, lubricants evolve even after the engine has entered production. Motul explains that the introduction of turbocharged gasoline direct injection (GDI) engines, to meet emission regulations, produced fresh challenges for lubricant manufacturers. The main issue involves Low-Speed Pre Ignition (LSPI), where combustion originates from a thin film of oil on the cylinder walls, rather than the spark plug. The engine management system, therefore, cannot do anything to prevent this extremely harmful situation. The only thing a workshop can do in response is to make doubly sure that the oils used comply with OEM specifications.

When selecting modern oils, prioritise the OEM specification over ACEA/API and even viscosity ratings. Be wary that subtle wording is also used between lubricant blenders to differentiate products that are endorsed by an OEM and those that are not but meet the same specifications. Always use well-established brands from a trustworthy factor.

Belt In Oil timing belts are also causing huge headaches for engines thus equipped. A professional engine rebuilder told us that, apart from having concerns about the belt itself, oil condition is a factor in premature failure. Not changing the oil on time, or running the level excessively low, degrades the lubricant to such an extent that the timing belt suffers. Eventually, the teeth detach and end up collecting within the oil pump, causing oil starvation. This is happening on surprisingly youthful cars, so be wary if you maintain such engines that possess BIOs. Additionally, check that the OEM belt replacement interval has not been reduced.

Therefore, when working on GDI turbocharged engines especially, be extra vigilant that the oil you use provides the necessary protection against LSPI and for BIO timing systems. Motul highlights that its Specific 948-B is approved by Ford to be used in the 1.0-litre petrol EcoBoost engines.

Research lots, pour once. Best practice dictates that you match the appropriate lubricant with the vehicle and avoid second-guessing.

Claims made on the packaging – should you be concerned?

Especially as oils are becoming ever more bespoke and making the wrong choice can have severe consequences, the oils must perform as their blenders claim. It is also why the Verification of Lubrication Specifications (VLS) investigates and acts upon misleading marketing claims. Far from punishing the industry, more positive aims include educating marketers and manufacturers on compliance, thus raising UK lubrication industry standards.

Therefore, the VLS says that, absolutely, garages should be concerned about claims made on oil packaging. The industry body explains that the use of performance marketing claims within the industry is complex and, sometimes, lacks consistency. This may explain why most complaints that the organisation has received over the past decade involve misleading statements.

To help workshops, the VLS publishes guidance to bring clarity and consistency about marketing claims. Instead of saying that a product is approved by a manufacturer, some oil companies employ alternative terms, such as ‘meets the requirements of’, or ‘suitable for use in’.

While these claims fall short of formal (and potentially costly) OEM approval, the lubricant blender makes an informed, professional judgement, based on supporting technical evidence as to the suitability of a given lubricant to a stated application. This can be because:

a. An approval exists on the formulation being used but the blender has decided not to pursue formal individual approval.

b. An approval is not possible technically, such as where claims are self-certified and no organisation can grant approval.

c. The specification is technically obsolete, or some tests are unavailable. Yet, based on a technical judgement with previously tested materials, the blender can be confident that the product would meet the OEM specifications.

d. The lubricant marketer, or its additive supplier, has sufficient robust and relevant supporting data for
the recommended application to support the claims. This should be based on engine test data against the requirements of the OEM specifications and/or data from substantial field trials, where appropriate.

So, the subtle choice of a few words makes all the difference. Even so, the VLS confirms that the lubricant marketer, or manufacturer, remains responsible for justifying any marketing claims with a robust technical source. Should workshops be unsure, the VLS encourages the use of lubricant manufacturer online databases, or technical helplines. Alternatively, workshops can consult the vehicle manufacturer or contact VLS for advice directly on 01442 875922.

High-quality engine oil flush additives are especially useful to help the fresh lubricant last until the next drain interval.

Additionally, Castrol has agreed to a five-year deal with the Ford Motor Company not only to be the brand’s recommended lubricant supplier in Europe but the two companies will also continue to co-develop automotive fluids until 2028. Consider that many other engines employ BIO too, such as cars made by Stellantis. A quick way of checking is to remove the oil filler cap and take a look inside.

The consequences of getting it wrong…

Motul warns that garages could be held liable for using incompatible oil, especially if the warranty is voided. It is easy to think that nobody will notice, until the damage takes place, but it is worth noting that independent laboratories are employed to test used sump oil and provide reports that can be used as legal evidence. This could connect, for instance, a blocked DPF with a high SAPS oil.

Some oil additives are useful to delay mechanical repairs.


UFI reminds us that the specified oil cannot do its job properly, if low-grade, or incorrect filtration is employed. Apart from containing suitable filtration media, an OEM spin-on filter will contain an anti-drain back valve to guard against oil starvation on start-up. The bypass valve will also be calibrated for that particular application to open at pre-set pressures, should the filter become blocked. Picking an incorrect filter, while it might fit physically, can be as damaging as fitting a very low- quality white box item.

Other additives help to fortify and enhance the lubricant and are especially useful if the vehicle is used under extreme conditions.

Comma adds that the incorrect oil can also reduce performance and fuel efficiency. Internal deposits, including sludge, are also more likely, as are oil leaks.

Keeping modern, modern…

Selecting the right oil is not always easy. For cars, produced within the last decade, check that any lubricant you use is compatible with the manufacturer’s specification. This ensures that the oil complies not only with the basic specifications, such as viscosity and API/ACEA ratings, but also contains extra ingredients that the manufacturer decrees that that engine needs. Motul advises that it is essential to select a reputable lubricants company, because many claims are being made that are impossible technically.

While most oil blenders have oil checkers, some of them quote a huge range of oils for a single application, even for modern engines. Usefully, the Motul Oil Selector ( lists oils not randomly but in priority order, based on technical preference. Comma is also so confident of its product recommendation site, CommaOil. com, that it backs it up with a 100% Compatibility Guarantee promise.

Dealing with golden oldies…

Workshops are seeing older vehicles, for which manufacturer lubricant specifications have either expired, or no longer exist. In these cases, Motul comments that garages should use older formulations that are suited for vehicles of the appropriate era, because they contain bespoke additive packages that provide the necessary level of protection and performance. Additionally, as older engines tend not to possess the tight clearances of more modern units, it is unwise to select thinner oils.

Formulations for historic vehicles vary considerably between manufacturers. Therefore, consult the owner about the intended usage patterns and be wary that drain intervals for older cars are comparatively short.

Garages are also reporting that more car enthusiasts are shunning DIY and sending historic vehicles to workshops
for routine maintenance work. Typically these cars are over forty years-old and require multigrade 20W50 engine oils. Naturally, the original low-detergent formulations have changed considerably over the years and blenders have realised that this is an extremely profitable part of the market. Consequentially, the choice for 20W50 is immense. Yet, many of these products possess API/ACEA ratings that are long obsolete, or even no ratings at all. Therefore, match the oil with how the car is used. Should the owner bumble to and from local car shows every year and the engine is in a mild state of tune, then do not worry too much about adding any 20W50 from a reputable blender. Yet, should the car tow, or is driven on motorways for long distances, then consider a higher specification semi-racing 20W50 that will retain its viscosity better at high temperatures. Should you be unsure, approach the lubricant blenders’ technical department for advice, especially if the company is like Comma, which offers several 20W50 oils within its range.

Picking up Motul’s earlier point about anti-wear additives for older engines again, consider that older, non-catalysed cars require high levels of anti-wear additives that are either not present, or exist in very limited quantities, in modern engine oils. A popular topic in old car circles is ZDDP, an older- generation but crucial anti-wear additive that deposits a sacrificial wear coating on certain parts, such as flat tappets. Motul highlights that a particularly high ZDDP concentration does not necessarily provide greater protection; it can even be counterproductive, especially when it can impair the effectiveness of other additives.

Avoiding grinding gears…

While much discussion focusses on engines, it is easy to forget other fluids. Using incompatible oils in other components can also be ruinous. Just like engine oil, many car manufacturers state that other fluids must comply with their OEM specifications. Where an international standard is quoted (such as GL4, or GL5 for gear oils), this should also be followed. In this case, a technician should not presume that a GL5 gear oil is compatible with GL4, despite the viscosity being the same. This is because the extreme pressure additives used in GL5 can corrode yellow metals employed in a gearbox/differential that needs GL4. Even so, Motul confirms that its gear oil complies with both GL4 and GL5, because the additives used are chosen carefully not to harm yellow metals.

Interestingly, the three most recent cases that were investigated by the Verification of Lubricant Specifications (VLS) all involved gear oils. SCT Lubricant’s Fanfaro 75W-90 Max 6 GL-5, Granville’s 75W-90 and Westway Lubricants 75W-90 Synthetic Gear Oil failed to meet their quoted viscosity specifications. We should add that all of these companies reacted and complied quickly to rectify the VLS’s findings, by identifying and disposing of the affected products and taking steps to ensure that future blends of these oils deliver on their claims.

Other considerations…

As with engines, manual gearboxes and differentials, pouring incompatible fluids into automatic transmissions, dual-clutch gearboxes and hydraulic steering and suspension systems can spell disaster. On those systems especially, incorrect oils damage the multiple rubber seals, causing leaks and ultimate failure. Therefore, make doubly sure that whatever fluids you use are suitable for the relevant component.

‘Sealed for life’ is another issue, especially with automatic transmissions. Like engine oils, some specialist flushes dissolve contaminations and hold them in suspension. JLM Lubricants says that its Automatic Transmission Flush performs this task and, once refilled with fresh fluid, the gearbox should run cooler, last longer and shift more consistently and crisply. As UK distributor of the JLM Lubricants portfolio, Kalimex supplies the blender’s Automatic Transmission Stop Leak & Conditioner additive that helps to restore existing fluid’s frictional properties and helps to soften and swell worn and hardened seals, which can help fix annoying leaks.

Some fluids are more specialist and may not be as widespread as more common lubricants.
About Autotechnician
Autotechnician is a magazine published nine times a year, delivering essential information to independent garage owners and technicians in the UK. Delivered both digitally and in print, autotechnician provides readers with technical, training, business advice, product and news, allowing our readers to keep up to date with information they need to run and work within a modern workshop.
Aftermarket Media Solutions Ltd, The Joiners Shop, Historic Dockyard Chatham, Kent ME4 4TZ
T: 01634 816 165
Company no. 09625886
linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram