Rolls-Royce and Bentley specialist Flying Spares has announced the reintroduction of RR363 brake fluid, suitable for Silver Shadow and all previous models.

The reintroduction of this fluid follows rumours that original supplier Castrol is no longer able to supply it, and is the result of over two years of patient chemical research. Developed by a partner which Flying Spares has identified as “a leading brake fluid manufacturer”, the new RR363 fluid has been tested as producing reduced rubber swell and a higher boiling point than the Castrol original.

RR363 is a DOT3 replacement developed for Rolls-Royce, when it was found that DOT3 didn’t provide sufficient lubricity for the Silver Shadow’s Citroen-derived braking system. Rolls-Royce and Castrol developed a fluid with an additive derived from castor oil for added lubricity.

Flying Spares advises that RR363 is also suitable for use in pre-1966 Citroen hydraulic systems which would originally have used LHS and which have a black reservoir. The two fluids should not be mixed, and you must drain all LHS prior to using RR363. RR363 is not compatible with the mineral based LHM used in post 1967 Citroens, which have green componentry. For more information visit

Brake fluid