FZG 12

[0402134140]

Gents,
1. If a manufacturer of gearboxes says lub. oil should be according FZG 12 class. How is this related towards lub oil properties, without being a lub oil supplier, what special properties I have to look for.
2. Heared rumours that there are more FZG clases then upto 12 : is this correct and how much clases are that?

Willem the gearbox user.

 

[Carburize]

The FZG test is a method to rate the ability of a gear oil to resist scuffing (scoring) of the gear teeth. The test consists of a pair of specially made gears which are tested through a series of load steps and are classified by an FZG number representing the maximum load step at which they prevent scuffing in the test. The test is covered by ISO 14635 and ASTM D 5182.
If you specify a gear oil to a certain viscosity and FZG number from manufacturers such as ExxonMobil they will have suitable gear oil available.