AMSOIL Protects Gears

AMSOIL Protects Gears Despite Water Contamination

Water and gear lube don’t mix, but in some situations you can’t help exposing your vehicle to water.

When you launch your boat at the landing, for example, the differential can be submerged for several minutes, depending on how quickly you’re able to launch or load your boat. During this time, water can slip past the differential seals and contaminate the gear lube. Water contamination can also be a challenge if you go off-roading or mudding.

And, for obvious reasons, you can’t avoid submerging your marine motor’s lower unit in water, either. Just like an automotive differential, water can breach the seals and contaminate the gear lube in the lower unit.

Gear lube contaminated with water can fail to protect

Water contamination is bad for several reasons.

Viscosity loss – A lubricant’s viscosity is its most important property. While viscosity is defined as resistance to flow, it’s helpful to think of it as the lubricant’s thickness. Your vehicle’s differential and your marine motor’s lower unit are designed to use a gear lube of a specific viscosity for optimal wear protection. Water can reduce the gear lube’s viscosity below what the manufacturer recommends, reducing wear protection.

Foam – A film of gear lube forms on the gear teeth it protects. This fluid film absorbs pressure and prevents metal-to-metal contact. Water contamination, however, invites the formation of foam. As the foam bubbles travel between gear teeth, they rupture under the intense pressure, leaving nothing behind to guard against wear. Eventually, the gears can wear out and require replacement.

Sludge – Water produces sludge, which inhibits heat transfer and increases lubricant temperature. Elevated temperatures speed chemical breakdown (known as oxidation). The faster the lubricant breaks down, the sooner it fails to provide adequate protection – and the sooner it must be changed, wasting money.

Rust formation – Water contamination invites rust formation on metal surfaces. Rust can flake off and circulate throughout the gear lube, where it acts like sandpaper and scours bearing and gear surfaces.

Severe service worsens the problem

Gear lube contaminated with water is especially problematic in vehicles used for towing or hauling (and if you’re towing a boat to the lake, your vehicle obviously fits the description). Towing and hauling increase gear and bearing stress while increasing lubricant temperature. These severe driving conditions place even greater demands on the gear lube, underscoring the need to use a high-quality lubricant to maximize differential life.

Marine motors also operate under extreme conditions that further stress the lubricant. Frequent throttle bursts concentrate tremendous pressure on the pinion gear and the forward and reverse gears. The gear lube fluid film can rupture, especially if it’s been weakened due to water contamination, leading to metal-to-metal contact.

AMSOIL synthetic gear lube offers a solution

Avoiding contact with water is impossible for some enthusiasts. That’s why AMSOIL formulates its synthetic gear lubes to deliver excellent protection despite water contamination.

With AMSOIL synthetic gear lube, you can rest assured your vehicles and marine motors are protected and equipped to handle whatever conditions you throw at them.

*Based upon AMSOIL testing of AMSOIL Synthetic SEVERE GEAR® 75W-90 and Long-Life 75W-90 Synthetic Gear Lube in ASTM D892.

**Based upon AMSOIL testing of AMSOIL Synthetic Marine Gear Lube 75W-90 in ASTM D892.

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