How is viscosity chosen for differential gear oil?

Viscosity is one of the most essential differential gear oil properties. Usually, it’s mentioned in a component’s maintenance manual. In case if there is no manual or a machine works somewhat differently, there are special methods for viscosity grade selection. Most methods involve such criteria as load, speed, and temperature.

What kind of oil to use for rear differential?

I’m about to change out the oil today. Click to expand… I believe the multi-weight atributes would be the same as with engine oil. 75 is the cold viscosity and 90 is the hot viscosity, so it should act like 75 weight oil when cold and 90 weight oil when hot.

Which is the best Lube for locking differentials?

Mobil 1 Synthetic Gear Lube – 75W90 is a high-performance universal synthetic gear oil, the viscosity grade of which meets the requirements of the modern passenger car transmissions that work in all operating conditions, including gears with locking differentials.

What are the different grades of gear oil?

There are two separate grading systems for gear oils. For universal, or automotive, gear oils there are two sets of standards. Those which are destined for use in transmissions are graded according to SAE standards. You might, for instance, see 80W-90 gear oil or 75W-140 gear oils on the shelves.

What’s the difference between gear oil and single grade oil?

Essentially, the first number of a multigrade oil, preceding the W, is the performance at 0°C while the second number rates it’s performance at 100°C. So a 75W-140 gear oil has similar performance to an SAE 75 gear oil while at 0°C. The single grade oils performance would only be measured at 100°C.

How is viscosity chosen for differential gear oil?