AMSOIL 75W-90 LONG LIFE 100% SYNTHETIC GEAR LUBE

AMSOIL 75W-90 Long Life 100% Synthetic Gear Lube delivers extended-drain gear protection for differentials, manual transmissions, and transfer cases across everything from Ram 2500 rear axles to Kenworth T680 drive axles. It is engineered to go up to 500,000 miles in Class 8 line-haul trucks and 100,000 miles in passenger vehicles under normal service, cutting maintenance intervals dramatically compared to conventional gear oils.

Differentials and gear sets operate under extreme pressure. Hypoid gear designs in most rear axles produce a sliding, shearing action that breaks down conventional gear oil quickly, thinning it out and leaving metal surfaces vulnerable. Towing, hauling, steep grades, and hot climates accelerate the problem. The result is accelerated wear, increased operating temperatures, and gear oil that needs to be changed far more often than most owners realize.

SHEAR-STABLE PROTECTION THAT HOLDS ITS VISCOSITY
Conventional 75W-90 gear oils lose viscosity over time as mechanical shearing breaks down their molecular structure. Once the oil thins, the protective film between gear teeth and bearing surfaces weakens. AMSOIL Long Life Synthetic Gear Lube uses a shear-stable formulation that resists viscosity loss from mechanical activity, maintaining its protective film throughout the entire drain interval. With a kinematic viscosity of 15.7 cSt at 100°C and a viscosity index of 143 (ASTM D2270), this gear lube holds its grade and keeps working where conventional oils fall off.

500,000-MILE SERVICE LIFE IN OVER-THE-ROAD APPLICATIONS
This is not a typical gear oil with a 50,000-mile ceiling. AMSOIL Long Life 75W-90 is specifically engineered and approved for drain intervals up to 500,000 miles or five years in heavy-duty Class 8 line-haul applications, following OEM recommendations. It meets Dana SHAES 256 (formerly Eaton PS-163) for 500,000-mile service and Dana SHAES 234 (formerly Eaton PS-037) for 250,000-mile service. For cars, SUVs, and light trucks like the Toyota Tundra, Ford F-150, or Chevy Silverado 1500, the normal service interval extends to 100,000 miles. Vocational and delivery trucks can follow OEM synthetic oil intervals up to 120,000 miles or three years. Premium synthetic base oils and high-performance additives resist oxidation and chemical breakdown, which is what makes these intervals possible without sacrificing gear and bearing protection.

COLD-TEMPERATURE FLUIDITY FOR ALL-SEASON USE
Thick, sluggish gear oil at startup robs efficiency and makes cold-weather shifting feel notchy and resistant. AMSOIL Long Life 75W-90 has a pour point of -48°C (-54°F) and a Brookfield viscosity of 109,000 cP at -40°C (ASTM D2983), flowing readily in temperatures that would turn conventional 80W-90 gear oil into something closer to molasses. That improved cold-flow reduces energy lost to internal friction during warmup and contributes to better fuel economy over the life of the oil. If you run a truck or SUV through northern winters, this gear lube moves when conventional oils do not.

RUST, CORROSION, AND SEAL PROTECTION
Moisture contamination is a constant threat in differentials, especially in vehicles that see temperature swings, short trips, or seasonal storage. AMSOIL Long Life Synthetic Gear Lube resists acids and actively protects against rust and corrosion to keep internal components clean. It also conditions seals to help prevent leaks and extend seal life. Copper strip corrosion testing (ASTM D130) returned a 1B rating at 121°C over three hours, confirming excellent compatibility with yellow-metal components found in synchronizers and bushings.

REPLACES CONVENTIONAL 75W-90 AND 80W-90 GRADES
AMSOIL Long Life 75W-90 directly replaces both 75W-90 and 80W-90 viscosity grades from competitors. It is compatible with most limited-slip differentials. If limited-slip chatter occurs, add AMSOIL Slip-Lock friction modifier additive. The gear lube is compatible with other synthetic and conventional gear oils, though mixing will shorten the extended drain interval and reduce performance benefits.

SPECIFICATIONS AND APPROVALS
AMSOIL 75W-90 Long Life Synthetic Gear Lube meets API GL-5, API MT-1, MIL-PRF-2105E, Dana SHAES 234 (250,000-mile), Dana SHAES 256 (500,000-mile), Dana SHAES 429A, Mack GO-J, Mack GO-J+, and Meritor 0-76N. It also satisfies hypoid gear oil specifications from ZF TE-ML 07A and 08 for foreign and domestic applications, and can be used where API GL-4 lubricant is recommended. This covers differentials in GM, Ford, and Chrysler trucks as well as foreign manufacturers.

SERVICE LIFE
For cars, SUVs, and light trucks: drain at 100,000 miles under normal service or 50,000 miles under severe service, or per the owner's manual, whichever interval is longer. For heavy-duty Class 8 line-haul: follow OEM drain intervals up to 500,000 miles or five years, whichever comes first. Vocational and delivery applications support up to 120,000 miles or three years. Heavy-duty off-road applications support up to 100,000 miles or two years. AMSOIL does not support extended drain intervals where water contamination occurs. Change gear oil more frequently in dusty or dirty conditions unless the gear system is properly sealed with membrane-type breathers.