Carry That Weight

Many people overstress their vehicles in the summer, pulling trailers, campers or fifth-wheels with boats, sometimes exceeding their rated towing limits. Commercial vehicles often spend their lives in severe service. Severe-service conditions and hot summer temperatures place extreme pressure on transmissions and differentials.

Modern trucks and SUVs boast more horsepower and torque than their predecessors, subjecting their differentials to increased levels of stress and heat. Gear oils must provide adequate wear protection, while also providing maximum fuel efficiency.

Thermal Runaway

The extreme pressures and temperatures generated by modern vehicles can lead to a serious condition known as “thermal runaway.” As differential temperatures increase, gear lubricants lose viscosity and load-carrying capacity. When extreme loads break the lubricant film, metal-to-metal contact occurs, increasing friction and heat. This increased friction and heat, in turn, results in further viscosity loss, which further increases friction and heat. As heat spirals upward, viscosity spirals downward.

Thermal runaway is a vicious cycle that leads to irreparable equipment damage and ultimately catastrophic gear and bearing failure.

The AMSOIL “Tow Package”

AMSOIL SEVERE GEAR® Synthetic Gear Lube and Signature Series Synthetic Automatic Transmission Fluid provide maximum protection in demanding environments such as towing, hauling and commercial use, providing increased lubricant film protection and reduced wear at elevated temperatures.

Field Proven

To demonstrate its effectiveness in severe service, Signature Series Multi-Vehicle Synthetic ATF was installed in Las Vegas taxi cabs. The vehicles routinely encountered demanding stop-and-go driving loaded with passengers and cargo, while the desert environment presented extremely hot ambient temperatures, placing enormous strain on the fluid.

Following 180,000 miles (289,682 km), a transmission was selected for analysis. The Aluminum Beaker Oxidation Test (ABOT) is an industry-standard test used to determine a transmission fluid’s oxidation resistance, which is a good indicator of its service life. Testing by an independent, third-party lab revealed that after 180,000 miles (289,682 km) in severe service, Signature Series Multi-Vehicle Synthetic ATF resisted oxidation longer than required for new fluid to meet the Chrysler ATF+4 specification.

In addition, components, including the valve body and clutch plates (pictured), were virtually free of damaging sludge, deposits and wear, confirming the lubricant’s high level of protection for severe-service applications. Upgrade your vehicle to AMSOIL protection this summer to protect your towing rig.

The transmission’s valve body is clean and virtually sludge-free following 180,000 severe-service miles (289,682 km). The clutch plates demonstrated only trace discoloration and earned a rating of “good,” the highest possible, for deterioration/wear.

SEVERE GEAR Synthetic Gear Lube

• Controls thermal runaway
• Features superior film strength
• Provides rust and corrosion protection
• Helps reduce operating temperatures
• Easy-pack reduces mess and hassle when performing tricky gear-lube changes

Signature Series Synthetic Automatic Transmission Fluid

• Specifically formulated for severe-service towing and heavy hauling
• Delivers reserve protection against extreme heat
• Maintains cold-temperature fluidity
• Superior friction durability for smooth, reliable shifts
• Easy-pack reduces mess and hassle when performing tricky lubricant changes