Motul Gear 300 LS 75W-90 is a 100% Synthetic – Ester based gear oil for gearboxes and limited-slip differentials, and it is sold in a 1-liter container. The manufacturer lists it to API GL-5. Its formula includes a special friction modifier to avoid noisy or dragging limited slip differential, which is the main reason to choose the LS version over the standard Gear 300 for an LSD-equipped drivetrain.
Against stock fluid or a cheaper mineral gear oil, the case rests on shear stability and cold behavior. The manufacturer cites very low shear loss by the severe test KRL 20H, which helps the 90 grade hold under heavy loads. It also claims improved transmission efficiency compare to a 75W-140 grade. Owners on user forums have described it as a clear step up from earlier fills that felt notchy, though one forum poster reported that motul doesn't shift well when cold, so results depend on your climate and the OEM fluid you are replacing.
The manufacturer's listed uses are mechanical transmissions, synchronised or non-synchronized gearboxes, transfer gearboxes, and hypoid differentials with limited slip, which makes it a fit for track, rally, and AWD performance builds. Owners on user forums have run it in BMW, VW, Toyota, and Range Rover differentials. For a DIY drain and fill, the job is straightforward when there are no cooler lines to flush, but loosen the fill plug before draining and fill until fluid overflows. Search terms this fits include Motul Gear 300 LS 75W90 limited slip differential fluid, GL-5 synthetic gear oil, and manual transmission fluid change.
The manufacturer's LS formula contains a friction modifier intended to prevent noisy or dragging limited-slip differentials. Opinions on user forums differ: some owners say the non-LS Gear 300 is acceptable in an LSD, while others argue it lacks the friction modifier an LSD needs. Confirm your requirement in the owner's manual.
The manufacturer's documentation describes manual gearboxes, transfer cases, and limited-slip differentials, and it does not specifically list dual-clutch units. Owners on user forums disagree on DSG use, so check your owner's manual for the required fluid specification before filling.
Changing this fluid is a moderate DIY job that needs a drain plug wrench, a fill pump or syringe, a catch pan, and a way to lift or access the drain and fill plugs safely. Owners on user forums recommend loosening the fill plug first, so you can confirm it will open before draining. Service documentation for some applications calls for replacing aluminum crush washers, so have new ones on hand. Refill until fluid begins to flow out of the fill hole, then reinstall the plug.
