It is not recommended to mix old and new power steering fluids. Mineral oil-based and synthetic steering fluids are generally incompatible; mixing them may lead to issues such as increased foaming, accelerated oxidation, or seal swelling. When replacing the fluid, the old fluid should be completely drained, and the model specified in the vehicle manual (such as ATF, CHF, or special synthetic oil) must be strictly followed. For example, some German cars require Pentosin CHF 11S, while Japanese cars may be compatible with fluids meeting the Dexron III standard. If temporary replenishment is needed, priority should be given to products of the same brand and model as the original fluid, and long-term mixing should be avoided. Regularly checking the fluid condition (immediate replacement is required if the colour darkens or impurities appear) can extend the life of the steering system. The maintenance cost is usually between 300 and 800 Malaysian Ringgit, while neglecting maintenance may cause damage to the steering pump or rack, with repair costs potentially exceeding 1000 Malaysian Ringgit.
