RalliSpec LogoRalliSpec Group N Car at LSPR
> home / catalog / lubricant / motul gear300

Gear 300 75W90

Motul Gear 300 transmission oil is an ester based full synthetic formulated for high performance and racing vehicles. Works extremely well in Subaru 5-speed and 6-speed synchronized transmissions (non-limited slip formula). The LS version has friction modifier additives for plate type limited slip diffs.

Usually ships in 2 to 3 days. Ships UPS Ground only.

Manufacturer: Motul

What is the color of this Gear 300 fluid? It is amber in color.

What is the difference between Gear 300 and Gear 300 LS? The LS formulation has added slip modifiers that allow clutch type limited slip diffs to function more effectively. However, the use of the standard Gear 300 is preferred in a synchronized transmission because the slip modifiers can reduce synchronizer performance. Therefore in a synchronized AWD transmission fitted with a clutch type front or center LSD some experimentation may be necessary to determine which fluid will give the best overall performance. Subaru 5-speed transmissions seem to be particularly sensitive to fluid selection due to the fact they are often being pushed to their limits and suffer from high operating temperatures.

What do the "GL" ratings mean? The GL rating is generally an indication of the level of extreme pressure(EP) additives that the oil contains. GL-4 oils contain a maximum of 4% EP additives. GL-4 oils are specified for synchronized transmissions and differentials that do not contain a hypoid differential (at least not one with a large pinion centerline offset). GL-5 oils contain a maximum of 6.5% EP additives and is required with most hypoid differentials. Transmissions like the Subaru 5MT and 6MT contain both synchronizers and a hypoid differential and therefore specify a GL-5 oil but require specific gear oils designed to work with the synchronizers. Motul Gear 300 is a GL-5 gear oil that meets the requirements for this type of application very well and is what we recommend for synchronized Subaru transmissions. Some oils are specified as GL-6 although this rating is no longer in general use. GL-6 oils contain up to 10% extreme pressure additives and are designed for very heavy loading, high shock, and the high sliding speeds of a hypoid gear with significant pinion offset.

What should the oil change interval be? It will depend on the type of operating environment. A high performance road application where the gearbox or differential is heavily stressed should probably change the fluid every 15K miles. The addition of a clutch type limited slip diff will necessitate even more frequent changes due to the contamination of the oil with metallic or carbon dust generated by friction plate wear. In a motorsport application it should probably be changed after every event or even mid event if it is an endurance race or long rally.