Regarding the fluids used in manual transmissions, what can be stated?

Manual transmissions vary in their fluid requirements based on design and manufacturer specifications. Some manual transmissions do indeed require specific types of motor oil instead of gear oil. This is particularly true for modern vehicles that are designed to use lighter viscosity fluids to enhance performance, improve fuel efficiency, and provide better shifting characteristics.

Additionally, while many older manual transmissions traditionally used 80w-90 gear oil, this is not a universal standard. Therefore, it is essential to refer to the manufacturer's guidelines for the specific vehicle to determine the correct fluid type. This variability is why having a statement that some manual transmissions may require motor oil is accurate, as it acknowledges the diversity in fluid requirements across different vehicles.