SAE 90 : They are high-featured mineral-based gear oils developed for all kinds of vehicle transmissions, gearboxes and differentials operating at low pressures.
API GL -4 :In hypoid gears operating under heavy service conditions without shock loading.
SAE 90 API GL-4 INDUSTRIAL GEAL OIL
The formula and manufacturing technique of the engine oil, which is produced by going through various reactions of multiple raw materials, can be found in the prepared pdf file.
* Process additive detailed list.
* Process temperatures and additive amounts.
* Processing time, detailed details.