Sinclair 80W-90 GL-5 Gear Oil

Sinclair Conventional Gear Oils Industrial Lubricants and Greases

Sinclair 80W-90 Gear Oil is formulated specifically for multipurpose, extreme pressure applications, such as conventional differentials, gear boxes, limited slip rear axles, manual transmissions and hypoid gears. Formulated with only the highest quality lubricant oils and our most advanced additive systems that include anti-wear, anti-friction, and extreme pressure agents, along with corrosion and oxidation inhibitors.

Other benefits include:

  • Excellent wear protection, especially under operating conditions of extreme pressure and high torque.
  • High thermal breakdown resistance.
  • Prevention of, rust, foaming, and corrosion.
  • Smoother and quieter operation.

Robust Anti-Friction, Anti-Wear Chemistry

Sinclair friction and wear control is unsurpassed, with advanced molecules that bond to form a barrier-building shield that reduces friction and wear.

Stands Up to Even the Most Extreme Conditions

Get outstanding protection even in the most severe hot and cold climates, pressure, micro pitting, or oxidation.

Performance You'll Notice

OEMs are continuing to change driveline designs, and conditions of operations are growing more severe. So you need gear lubricants with outstanding load-carrying capability wherever extreme pressures and shock loading might occur. The technologically advanced driveline gear oils from Sinclair are formulated to meet the challenge of balancing protection, toughness and endurance.


Against load, shear and shock.


Excellent protection against wear and corrosion.


Long-lasting thermal stability means longer life for gear, bearings and seals.

Industry/OEM Specifications

API GL-5 Meets Requirements
Mack GO-J, GO-H, GO-G Meets Requirements
MT-1 Meets Requirements
SAE J2360, MIL-2105E/F Meets Requirements
Limited Slip Top Off/Service Fill Suitable for Use

Typical Properties

Brookfield Viscosity at -26°C, cP ASTM D2983 92,000
Color ASTM D1500 7
Flash Point °C ASTM D92 224
Flash Point °F ASTM D92 435
Gravity, °API ASTM D287 27.76
Pour Point °C (°F) ASTM D5950 -33°C (-27°F)
Specific Gravity @ 60°F (15.6°C) ASTM D4052 0.8885
Viscosity @ 100°C cSt ASTM D445 13.98
Viscosity @ 40°C cSt ASTM D445 130.9
Viscosity Index ASTM D2270 104

Container/Bulk Availability

55 Gallon Drum Product Number - 570-003
5 Gallon Product Number - 570-008
Available in Bulk