Lubricants and Fluids

F1 and WEC racing teams are closely aligned with lubricant and fluid manufacturers and almost all teams have technicians from their suppliers embedded in their teams such is the importance of lubricants and fluids to the performance of the race car. ExxonMobil are partnered with Red Rull, Shell’s relationship with Ferrari goes back through the decades, Gulf with Ford and later Porsche, Petronas are aligned with Mercedes, and of course Castrol were involved with TWR throughout the success Le Mans and IMSA programme during the 80s/90s. Prior to that Motul backed TWR’s winning ETCC racing with the XJS and continue to be heavily involved with motorsport at all levels including the Dakar Rally, the 24 Hours of Le Mans (cars, motorbikes), MotoGP and many others. This has great benefits for both parties, racing teams get a first-class sponsor with large marketing budgets, oil companies get fabulous worldwide exposure, but they also get a fabulous testing ground where they can collect lots of data and ultimately gain the information, they need to improve products. 

One of the main reasons behind car internal combustion engines becoming more reliable has been the technological advancements in oil. In particular, the development of synthetic oils. This has led to longer service intervals, improved engine efficiency and environmental benefits. When we think about it, the quality of oil is the most limiting factor in an engine. We only need to go back a few decades to know that engine manufacturing tolerances were not as good as modern engines, oil needed changing more frequently, and new engines required a ‘running in’ period. Modern synthetic oils have been a ‘game changer’ that said, it is still good practice to change your engine oil annually even if you are doing low mileage particularly if your journeys are short where the engine doesn’t reach optimum running temperature.

We have been working for several years with Motul as a performance partner for fluids and lubricants, we have always been impressed with their technology, quality and service levels. Motul even offer us a service for analysing our used racing oil which gives us excellent feedback on the status of the engine. This analysis is something that can be extended to road cars too. Motul also offer probably the widest range of lubricants and fluids available of any fluid manufacturer and includes their competition range. 

Lubricants and fluids may not seem an obvious performance modification or upgrade but in someways it could be argued that they are the most important upgrade of all and as one well known advert once described it, it is “liquid engineering”. 

We could go into a lot of detail with regards to engine oil as it’s large topic and one that perhaps we’ll return to in more detail in the future. Engine oil is one of several fluid components in the car, which include; gear box oil, differential oil, engine coolant, power steering fluid, clutch and brake fluid and lesser perhaps, washer fluid. 

As we know the majority of modern Jaguars use ZF transmission units. At Swallows we are authorised ZF agents and therefore use the recommend ZF Lifeguard transmission fluid when servicing your gearbox. Over time the build up of contamination can make the gear shift less responsive and eventually even sluggish. Once that starts happening, gear shifting will cause the gears to change too fast or too slow as you’re driving the vehicle. Added to which, with low transmission fluid in your vehicle, there will also be a temporary delay after you move the gear into reverse or drive, that’s because the gear shift cannot take place immediately if there isn’t enough transmission fluid pressure. In addition, keeping a transmission clean and operating correctly ensures a longer life. In race applications due to higher operating temperatures, we use Motul competition transmission fluid. 

Differential Fluid usually lasts longer than most other fluids. The life of differential fluid is variable and depends on the type of driving and use of the vehicle, but a major difference between other oils and differential fluid, is differential fluid usually is not filtered. Usually, differential fluid is changed after every 30k to 60k miles driven, all wheel drive vehicles typically need more frequent changes. We use Motul fully synthetic diff oil which is especially designed for high performance vehicles and contains special friction modifiers. 

In the September 2024 issue of Jaguar Enthusiasts magazine, we covered the differences in brake fluid in our track day preparation article, but generally speaking most modern Jaguars will be using DOT 4 as standard. We use and supply Tarox brake fluid with boiling point of over 300 degrees C which is suitable for road and track use. Typically brake fluid will be changed on every alternate service ie; every two years or around 24,000 miles depending on the service schedule. Over time, brake fluid absorbs moisture which reduces its efficiency and can lead to ‘spongy’ brakes. Regular fluid changes also helps to reduce corrosion. 

In power steering applications we also use Motul fully synthetic hydraulic fluid. Power steering fluid should generally be changed every 30,000 to 50,000 miles or every 2 to 3 years, whichever comes first and depending on the service schedule. Dark brown or black fluid is an indication of a need that the fluid needs changing. 

Coolant/Antifreeze plays an important role in the efficiency of modern cars for several reasons. It contains inhibitors that prevent rust, corrosion, and lime scale build up in the cooling system, which can damage the radiator, and engine block. Coolant also has a higher boiling point than water which can allow the engine to operate at a higher temperature and a lower freezing point that protects the engine in cold and freezing temperatures. Coolants also contains lubricants that reduce wear on moving parts in the cooling system such as water pumps. Motul also supply us with a range of coolants suitable for all applications. 

The choice of lubricants and fluids is hugely significant to the performance and the longevity of our Jaguars and as such are as important as any component that we have looked at in Mods and Upgrades.