RR363 Rolls-Royce Brake Fluid: What’s all the Fuss?

For any dedicated Rolls-Royce enthusiast, the subject of the RR363 Brake Fluid is more than just a technical discussion; it’s about the legacy of the marque.

When Rolls-Royce introduced the Silver Shadow series, they initially recommended the use of DOT3. Technically speaking, DOT3 does its job for the complex hydraulic systems of the Rolls-Royce Silver Shadow, Bentley T-Type, or the Corniche. However, post-1980 Corniches (from chassis 50001 onwards) required the green mineral fluid. The introduction of Silver Shadow and its siblings brought forth an unexpected issue: peculiar hydraulic rear height control ram noises.

In addressing this challenge, Rolls-Royce joined forces with Castrol Oils to develop the RR363, and the problematic squeaks were eliminated. This collaboration marked a significant advancement in the luxury vehicle industry.

While the RR363 might appear as a mere combination of DOT3 and caster oil, the underlying science is intricate. The viscosity disparity between DOT3/4 and caster oil makes them segregate over time, an issue Castrol adeptly resolved. They integrated a dispersant, ensuring the caster oil remains uniformly dispersed throughout.

The distinct formulation and legacy of the RR363 Brake Fluid make it our top recommendation for the sophisticated systems of Rolls-Royce and Bentley vehicles. Embrace it for a consistent, squeak-free driving experience.

Prestige Parts® isn’t just a name; it stands for quality and expertise in aftermarket parts for heritage and modern Rolls-Royce and Bentley vehicles. For those who share our passion for maintaining the legacy of these automotive masterpieces, we are your dedicated partner.

For a deeper technical insight, explore our RR - Technical Video Library or contact our knowledgeable team who is here to help: sales@introcar.com. To ensure your luxury vehicle gets the best care, get your top-quality RR363 Brake Fluid today!

In the Rolls-Royce fraternity, nothing seems to cause more controversy than Rolls-Royce Brake Fluid: Castrol RR363 hydraulic fluid. Any mention on a forum or chat room seems to generate acres of comment, with any number of views (some very vociferous). After all, RR363 is just a glycol-based oil, very similar to DOT3 and DOT4 synthetic oils. So why all the fuss?

Deep breath.

When the Silver Shadow series was introduced, Rolls-Royce originally recommended DOT3 brake fluid, and it’s true – you can use it without causing irrevocable damage to the complex hydraulic system of your Rolls-Royce Silver Shadow, Bentley T-Type or Corniche (take note, though, from chassis 50001 (1980) Corniche onward you must use green mineral fluid). Pretty soon after the Silver Shadow (etc.) was introduced, owners started to complain about funny knocks and squeaks, particularly from the hydraulic rear height control rams. To cure this, Rolls-Royce Motorcars Limited developed the Rolls-Royce Brake Fluid RR363 with Castrol Oils. RR363 cured the squeaks, and everyone lived happily ever after.

Except they didn’t.

Most people know that Castrol added a certain amount of castor oil to the glycol base. Well, DOT3 is cheap, and castor oil is cheap, why not mix a bit up at home? Job done.

Not quite. The problem is that the viscosity of DOT3/4 and caster oil is different. If you leave it in a jar (or in the reservoir of your Rolls-Royce or Bentley braking system) it will separate, and one oil will float on top of the other. If they’re separate, you won’t get the benefit of both parts. Castrol solved this by adding a chemical dispersant to the oil, which keeps the caster oil evenly dispersed through the base oil.

That’s why we recommend RR363 Brake Fluid, and our customers drive squeak-free Rolls-Royce motorcars… I hope this helps!