What is the best gear oil? Looking for an ideal for mechanics
Content
Criteria for evaluating gear oils for manual transmissions
Standard oils for manual transmissions have two main indicators that determine their ability to work in certain transmission units: API oil class and viscosity. These are the most common parameters in the classification of gear oils.
Mechanical transmission, in fact, is a set of heavily loaded gears, the shafts of which rotate in rolling bearings. Control mechanisms, wings and forks, are much less loaded. Therefore, no special emphasis is placed on their lubrication, since any transmission lubricant is usually sufficient for the normal operation of these mechanisms.
Synchronizers also play an important role in manual transmissions. The essence of the synchronizer is to align the speed of the mating gears before engagement. If the gears rotate at different speeds, it is problematic to create their engagement on the go. Usually, the failure of synchronizers is characterized by a tight engagement of gears with a characteristic metallic rattle.
The synchronizer works simply. Before pairing the gears, when shifting gears, first the synchronizer surface comes into contact with the side surface of one of the gears and, due to friction forces, equalizes the speed of rotation of both gears. After that, the gears engage easily and without extraneous sounds. But if there are too many anti-friction additives in the oil, then the synchronizer will begin to slide along the side surface of the gear. The rotation speed will not equalize. The box will start to malfunction.
It turns out that gear oils must meet the following criteria to the maximum extent:
- protect loaded gears from wear and scuffing;
- effectively lubricate rolling bearings;
- do not interfere with the operation of synchronizers and other control units;
- perform their functions for a long time.
The higher the quality of the combination of these evaluation criteria, the better the gear oil.
The best gear oils
The trend with gear oils is actually quite simple: the higher the cost of the oil, the better it will protect the manual transmission from wear and the longer it will last. However, do not forget that you need to select oil strictly of the class and viscosity that are recommended by the car manufacturer and that correspond to climatic conditions.
For example, oils of categories GL-3 and GL-4 (almost a complete analogue of domestic TM-3 and TM-4) are recommended for synchronized manual transmissions, in which, in the presence of hypoid gearing in the main gear, the load does not exceed 2500 MPa and 3000 MPa, respectively.
More technological lubricants GL-5 and GL-6 (TM-5 and TM-6) are able to protect the gears and bearings themselves more effectively, but are incompatible with some synchronized manual transmissions.
It is difficult to assess the quality of transmission oil for manual transmissions in the short term, since replacement intervals often exceed 60-80 thousand km. Therefore, below we list the manufacturers of gear oils that car owners speak well of:
- shell;
- eleven;
- Fox;
- Castrol;
- Liquid Moly;
- The motto;
- Mannol.
Among the domestic producers traditionally Gazpromneft, Lukoil and Rosneft are the leaders.
The best transmission oil for VAZ
Let's take a brief look at the best gear oils for AvtoVAZ vehicles.
- Zic. This Korean manufacturer of lubricants is confidently conquering the markets of the Russian Federation, especially in the community of VAZ car owners. Among gear oils, motorists speak well of G-FF class GL-4 synthetics. This oil is suitable for boxes of both classic models (from VAZ-2101 to VAZ-2107), and for later ones, the Samara, VAZ-2110 and Samara-2 (VAZ-2114) families. In more recent VAZ models, GF TOP class GL-4/5 synthetics are suitable.
- Agip. This little-known manufacturer is liked by most VAZ owners with a manual gearbox. The oil, although it belongs to semi-synthetics, but, judging by the reviews of motorists, it works well even in boxes of relatively modern models, such as Grant and Priora. Agip Rotra gear oil is available in a wide range of viscosities, but the most popular options are 75W-90 and 75W-80, which are optimal for the middle and northern strip of the Russian Federation. In regions with warmer climates, thick lubricants are used.
- Lukoil. Perhaps the most famous manufacturer of gear oils for domestic cars in the Russian Federation. Lukoil TM-5 of class GL-5 and with a viscosity of 85W-90 is most often used for Niva. Lukoil is also recommended to fill in with owners of other VAZ models. In motorist circles, there is an opinion that this oil is optimal in terms of price / quality ratio.
- Gazpromneft. Now it focuses mainly on the production of gear oils for automatic transmissions, but there are still a lot of simple lubricants for manual transmissions on sale. On the Internet, there are often reviews from the owners of Kalin, who speak positively about these oils.
- Rosneft. Oils of the Kinetic Hypoid line not only have the official approval of AvtoVAZ PJSC, but also collected a lot of positive feedback from car owners. Motorists note smoother shifting and oil retention in cold temperatures, which makes it easier to start driving in the winter.
Negative reviews about gear oils are mainly related to the wrong viscosity or grade, as well as the delay in replacement.
