Viscosity is the resistance of fluids against flowing. An oil film is formed between the two surfaces under pressure with viscosity and system parts are provided to work for long years without abrasion.
In many respects, synthetic oils have superior properties than mineral oils. Long life is one of them. Compared to mineral oils, synthetic oils as a general principle it can be said to have the better extended oil drain intervals. However, the oil change intervals are determined by the vehicle manufacturers (OEMs) after a series of tests. Compliance with these oil change intervals is the best in terms of equipment health.
PETDER serves free of charge regardless of quantity and distance throughout Turkey with its waste engine oil collecting organization. Waste producers may contact PETDER as the Authorized Establishment through the website www.petder.org.tr, via e-mail atikyag@petder.org.tr or via telephone 0212-229 39 99 to gain information or to have waste oil they collected in accordance with principals of regulation collected. The collecting process is monitored on satellite with central planning and is conducted by vehicles appropriate to EU standards and trained staff.
It is the API classification used for gear oils. Oil that contains additives to balance excessive pressure and pulsed load for hypoid gear type differentials running under heavy conditions and that fulfills MIL-L-2105 specifications. In GL-5, there are more overpressure additives and it is generally used under heavy work conditions. Unless otherwise specified, GL-5 should not be used in places where GL-4 is recommended. Because the sulphide in overpressure additive which is present excessively in GL-5 corrodes yellow metals.
The Association of Automotive Engineers (SAE) classifies automotive gear oils according to their kinematic viscosity values at 100 °C and their pumpability at low temperatures.
For example, the SAE 80W-90 in an automotive gear oil '90' describes the kinematic viscosity of this gear oil at 100 °C. As this number increases oil thickens, if the number decreases oil thins. The kinematic viscosity of '90' gear oil at 100 °C is between 13.50 and 18.50 cST while the kinematic viscosity of '140' gear oil at 100 °C must be between 24.00 and 32.50 cST. The number to the left of W (Winter) determines the performance of gear oil at low temperatures. Pumping temperature of '80W' gear oil is -26 °C while pumping temperature of '75W' gear oil is -40 °C.
Synthetic based oils are oils produced with chemical methods.
They are produced to lubricate in applications where traditionally obtained mineral oils cannot be sufficient.
Synthetic-based oils provide superior protection at higher temperatures than minerals, easier flow and pumpability at low temperatures , more stable film strength under extreme pressure and longer drain interval in difficult operating conditions.