Automobile transmission oil composition with improved low-temperature transmission performance

Abstract

The present invention provides a manual transmission oil composition containing a predetermined amount of polyalphaolefin (PAO) synthetic base oil and a predetermined amount of polyalkylmethacrylate having a number-average molecular weight of 300,000 to 400,000 as a viscosity index improver and thus having a high viscosity even at high temperatures and a low viscosity at low temperatures compared to other manual transmission oils having the same viscosity grade (SAE 75W85 grade).

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims under 35 U.S.C. §119(a) the benefit of Korean Patent Application No. 10-2010-0074076 filed Jul. 30, 2010, the entire contents of which are incorporated herein by reference.BACKGROUND[0002](a) Technical Field[0003]The present disclosure relates to an automobile transmission oil and a method of lubricating an automobile transmission using the oil. More particularly, it relates to a manual transmission oil composition containing a polyalphaolefin synthetic base oil and a viscosity modifier.[0004](b) Background Art[0005]In a typical vehicle, a transmission is installed between a clutch and a drive shaft or between a clutch and a final reduction gear. The transmission converts the engine's output by adjusting the speed and torque so as to drive the wheels with rotational speeds and forces suitable for operating the vehicle. A manual transmission changes the rotational speed and force transmitted from the engine through a...

AI Technical Summary

Benefits of technology

[0010]The present invention features an automobile transmission oil composition which is provided with a low viscosity at low temperatures, while reducing rattle noise and maintaining excellent transmission durability even at high temperatures. The transmission oil composition is useful for lubricating and operating various types of transmissions, including a manual transmission. According to an aspect of the present invention, an automobile transmission oil composition comprise

Problems solved by technology

If the viscosity of the transmission oil is significantly increased, such as during cold winter conditions, synchronization achieved by friction during contact is impeded, thereby reducing shifting performance.

However,