Gear systems must be cooled, lubricated, and protected by high-quality gear oils. Those same oils also flush away particles from the contact areas that can cause damage or excessive noise. These oils must also protect from high pressures and extreme temperatures to prevent unnecessary wear and tear on your differential or manual transmission. Gear oils have a duty to protect from elemental damage as well, like corrosion.

DO NOT try and use motor oil as a replacement for your gear oil. Motor oils have additives that clean byproducts from the combustion of the fuel in your engine. Motor oils do not have additives that protect from the high pressure that is created in your transmission or differential because of the way the oil is circulated in your engine. As a result, using either oil in place of the other would cause undesired results in the long term.

There are many types of protection in the additives for gear oils. Some manufacturers’ additives contain most of the protections. Others contain one or a few of them, depending on the quality of the additive. When looking for an additive for your gear oil, make sure that they offer the protection you may need the most. These are the most common types of protections that are given by oil additives.

Anti-wear or extreme pressure agents minimize the “boundary lubrication” damage. Boundary lubrication situations would occur when higher-than-normal pressure is being placed on the teeth of your gears, as in heavy acceleration or deceleration. Pour point depressants lower the temperature at which the oil stops flowing, or the “pour point.” As a rule of thumb, you always want your pour point to be about 20° F below the coldest expected temperature. Anti-foaming agents lower the partiality the oil has to foam when being spun and sloshed vigorously. When this happens, tiny air bubbles become trapped in the oil and reduce the lubrication and protection qualities of the oil. Viscosity index improvers reduce the tendency for the oil to change viscosity as its temperature rises. Friction modifiers are used in situations where there is a very high amount of pressure being placed on the gears and there is a need for a friction modifier to take some of the brunt, instead of the gears. Rust and corrosion inhibitors are necessary to protect your drivetrain’s components from — you guessed it — rust and corrosion.

Be sure you get the properties you need the most when choosing a gear oil additive. If you live in a place that never gets too cold, you may never need a “pour point depressant.” Be sure if your vehicle has equipment that is placed under high loads, like a locking differential, you have a friction modifier that would let that component perform at its best.

Visit Gear systems must be cooled, lubricated, and protected by high-quality gear oils. Those same oils also flush away particles from the contact areas that can cause damage or excessive noise. These oils must also protect from high pressures and extreme temperatures to prevent unnecessary wear and tear on your differential or manual transmission. Gear oils have a duty to protect from elemental damage as well, like corrosion.