SAE J306 VISCOSITY GRADES

SAE Grade	Minimum dynamic viscosity temperature	Kinetic viscosity	at 100°С, mm²/s
	150 Pa*s, °С Min Max
Winter
70W	– 55	4,1	–
75W	– 40	4,1	–
80W	– 26	7,0	–
85W	– 12	11,0	–
Summer
90	–	13,5	24,0
140	–	24,0	41,0
250	–	41,0	–

In addition to factory standards, API recommendations are important. But the requirements for modern
gear oils are very complex, so the API is only an approximate classification.

GL-1 (ISTEK) Mineral oils without additives or with anti-oxidation and anti-foam additives without EP
components for use, among other things, in manual gearboxes with low specific pressures and sliding
speeds. Cylindrical, worm and helical bevel gears operating at low speeds and loads.

GL-2 (ISTEK) Worm gears operating under GL-1 conditions at low speeds and loads, but with higher
requirements for anti-friction properties. May contain an anti-friction component.

GL-3 (ISTEC) These oils are used preferably in speed gearboxes and steering gears, in final drives and hypoid gears with low displacement in cars and trackless vehicles for the transport of goods, passengers and for non-transport work.

GL-4 These oils are used preferably in speed gearboxes and steering gears, in final drives and low
displacement hypoid gears in automobiles and trackless vehicles for the transport of goods and passengers and for non-transportation work. Hypoid gears operating at high speeds with low torques and low speeds with high torques.

GL-5 Hypoid gear oils with MIL-L-2105 C/D performance level. These oils are preferably used in hypoid bevel gears and bevel gears for final drives in automobiles and in motorcycle cardan drives and motorcycle speed gearboxes. Especially for hypoid gears with high axle offset. For severe operating conditions with shock and alternating loading.

GL-6 (ISTEK) High displacement hypoid gears operating under high speed, high torque and shock loading
conditions.

MT-1 Oils for highly loaded units. Designed for non-synchronized manual transmissions of powerful
commercial vehicles (tractors and buses). They have increased thermal stability.