Synthetics and Multi-Weight Oils. While old-timers may rely on the old standard SAE 90 weight gear oil, newer multi-weight oils, such as Amsoil’s 75W-140 synthetic, maintain their viscosity at ...

Bar’s Leaks Gear Repair can be mixed with all synthetic and conventional petroleum GL-4, GL-5, MT-1 gear oil grades, including 75W-90, 80W-90, 75W-140, 85W-140 and all others. Related Stories Gear ...

Since gear oil is thicker and more viscous, it is ideal for high-pressure applications. It is often labeled with viscosity ...

Gear oil is designed to protect vital components, including the gears and bearings in the drive axles and differentials, transmissions, industrial gear boxes and power take-off units.