A traditional GL-4 gear oil of any given viscosity has about ½ the level of phosphorus additive found in GL-5, so the surface tension bond is not as strong, and therefore, under heavy loads, brass stripping can occur over time ( wear of box parts). This means that the GL-4 offers slightly less overpressure protection. Therefore, for high speed hypoid gears API GL-4 doesn't really fit.
If GL-5 oil is used in a gearbox that requires GL-4, there will also be a process premature wear synchronizers and gears. This is due to the settling of copper present in GL-5 oil. In the latter, it is 4 times more than in oil API standard GL-4.
What to do if you can't find the GL-4?
Everything is very simple! An excellent replacement for GL-4 80W-90 gear oil will be SAE oil 50, which meets the CAT TO-4 specification. Interchangeability takes place here, since the operating temperatures are very similar, and, in the case of SAE 50, the level of copper does not exceed the mark indicated on the packaging of GL-4 80W-90.
What is the difference between gl 4 and gl 5?
TO fundamental differences, which nevertheless have some significance, both for the car and the buyer, can be attributed to:
- Operating ranges of the gearbox. API GL-4 is acceptable for use on cars with "stock" boxes that are not subject to high loads.
- different viscosity. GL-4 has a lower viscosity, both on a heated box and not.
- Anti-seize properties. In relation to the above boxes, it is a worthy option, as it has a balanced amount of copper and iron impurities. GL-5 has significantly more copper in its composition, which is sure to harm the low load range box.
- Price. This parameter in terms of differences gear oils affects solely the buyer/owner of the vehicle.
What oil to choose when changing the configuration of the car?
What to do if you put more powerful engine in the car or increased HP dramatically? A rational solution would be to use GL-4 synthetic oil. It also plays a role price category. How to understand that the oil is chosen correctly and its further use will not damage the box? Here everything should be left to chance or the feeling of "stubbornness" of the box. If this is the case, then it is necessary to replace the selected one with GL-5. The drained oil sample should be sent for analysis, and the new filled one should be analyzed over a similar period of time.
If the sample shows an excess of iron, then clearly GL-4 is not suitable. Gear oil GL-5, thanks to more high viscosity, creates an improved protective film, but the amount of copper impurity in the total amount of oil increases. So to say: - a double-edged sword.
If the only solution to protect the box from premature wear is the use of GL-5 oil, then a compensatory measure that will somewhat correct / reduce the amount of copper impurity dropping out will be a filter with a magnet.
Such replacement of the unit entails additional expenses, both in terms of conversion and traditional gear oils. The specificity of the re-equipment involves the replacement of both synchronizers and gears. If synchronizers can still be classified as Supplies, then the latter should be saved, and, in fact, use GL-5. It will be especially useful in cases where the power of the car increases. 100 hp and more.
The main difference and rationality of the purchase
Whatever one may say, the main difference between such oils is gear operating range. So, for example, API GL-4 is used under conditions of varying severity, and GL-5 is relevant for high-speed hypoid gears and drive axles, which, in turn, operate at fairly high temperature conditions alternating with short-term shock loads.
Establishing and maintaining extreme pressure properties is very important for any machine that may use any of the above synthetic oils. Choosing the right one in no way ends in buying and using the top class, even the same GL-5 API.
illustrative example
As good example you can take the popular affordable car Lanos. Pouring into his box too expensive oil seems absurd, and, as practice shows, it is irrational. The box, according to the principle of its functioning, refers to the average degree of load. Someone will say that it is better to fill in GL-5 and forget about it. As already mentioned above, this oil It has a high extreme pressure property due to the increased concentration of copper impurity. It is copper, of course, in excessive quantities, that literally in half a year will disable synchronizers and other driving elements. As a result, the potential owner will receive a damaged box and headache as additional article expenses.
API GL-4, in relation to the same Lanos, will cost a little more, since the frequency of scheduled oil changes differs from the above in a larger direction, but it eliminates the possibility of premature wear of the box elements.
Note! Waste oil, whether it be GL-4 or GL-5, cannot be reused in any vehicle component.
The difference mostly comes down to the additive formulation, GL-4 oils typically contain 3 to 4% EP additives and GL-5 4.5 to 6.5%.
In view of this, the GL-5 is recommended for heavier gears (e.g. hypoid gears) and also as a universal gear for most mechanical transmissions, which do not have synchronizers made of non-ferrous alloys in the design. This is due to the fact that the package of extreme pressure additives contains sulfur-phosphorus elements, which can cause corrosion of parts made of non-ferrous alloys.
Thus, GL-4 is typically used for synchronized gearboxes, and GL-5 for axles and gearboxes. For front wheel drive vehicles, because the fight against corrosion of synchronizers can go against the protection of final drive gears, because they are in the same block.
The gears are synchronized by pressing the blocking synchronizer against the gear cone - the oil film is squeezed out and the rotation speeds are compared. The problem is that in this case the lubrication becomes semi-dry and the problem is not corrosion, but wear, so each transmission manufacturer adheres to its recommendations here.
Many owners at the same time prefer to sacrifice possible corrosion of synchronizers in favor of greater extreme pressure properties (especially in the case of high loads), i.e. choose the specification GL-5, although the manufacturer prescribed GL-4. On this moment Texaco has API GL-4/GL-5 dual specification synthetic oils in its arsenal, being low viscosity, they provide good lubrication hypoid gear and non-corrosive to non-ferrous metals, as a result, can be used in cases of both specifications.
Many consumers are wondering: what is the difference between gear oils of API GL-4 and API GL-5 standards? In addition, manufacturers often lubricants indicate on their products compliance with both standards at the same time - API GL-4 / 5.
API GL-4 is specified for gear oils used in bevel and hypoid gears in gearboxes and drive axle assemblies operating under moderate speed and load conditions. API GL-5 standard - for high speed hypoid gears and drive axles operating under high temperatures and subjected to short-term shock loading.
Thus, in accordance with the classification, API GL-5 oils provide the best extreme pressure properties, protection under high loads and pressures. It is absolutely correct to say that API GL-5 oils cover the requirements of the API GL-4 standard. The problem is that the classification of gear oils does not take into account technological features a number of gearboxes.
If we trace the history of the development of gear oils, we can note that several decades ago, lubricant manufacturers used lead additives for wear protection. Subsequently, they were replaced by sulfur-phosphorus additive packages due to the fact that lead has a negative effect on environment. Sulfur was then observed to corrode parts made of copper and other soft metals. However, about 20 years ago, additive packages were developed to neutralize corrosion from sulfur-phosphorus additives.
The key point is the fact that on average in oils API categories GL-4 sulfur-phosphorus additives are half as much as in API GL-5 oils. Sulfur-phosphorus additives create a special protective covering on transmission parts. During operation, the contact between the rubbing elements occurs through this coating and thus the parts are protected from wear. However, when copper parts come into contact, this coating appears to be stronger than the surface of copper parts or other soft parts. As a result, not only the protective layer is worn, but also the surface of the soft metal element.
A number of studies have shown that when using API GL-5 oils in boxes where API GL-4 oils are required, copper in the used oil is 2-4 times more than using API GL-4 oils. As a rule, synchronizers are made of copper and are subject to increased wear, when using lubricants with high content sulfur-phosphorus additives. Some lubricant manufacturers, when specifying the API GL-4 / 5 standard, explicitly indicate that the product is not intended for gearboxes with synchronizers.
On the other hand, the API GL-5 standard no longer always meets the requirements modern technology, which caused the emergence of a new international standard SAE J2360. Accordingly, a natural question arises as to how API GL-4 / 5 gear oils, containing a moderate package of extreme pressure additives for synchronizer gearboxes, are good for use in other highly loaded units.
Lubri-Loy recommends that you carefully follow the vehicle manufacturer's recommendations when selecting gear oil. The Lubri-Loy range allows you to choose the best product to meet your requirements various manufacturers OEM original equipment.
Due to the fact that many modern boxes severely stressed, Lubri-Loy manufactures an API GL-4 oil from a fully synthetic base stock: Lubri-Loy® Premium Synthetic Gear Oils 75w90 API GL-4.
For the harshest operating conditions, including trucks, Lubri-Loy manufactures Lubri-Loy® Premium Synthetic 75w90 GL-5 Limited Slip Gear Oils, a fully synthetic gear oil. API GL-5, Meritor O76-N, International TMS 6816, Mack GO-J, SAE J2360 API MT-1 (PG-1), PG-2, MIL-L-2105E, Eaton Roadranger® 6 x L60-1.
Stable operation vehicle possible only when used in automotive oil assemblies High Quality. Transmission machine oils deserve closer attention of motorists, but now they use motor ones more.
Gear oil is used to lubricate the gears of vehicles in the transmission units - steering gears, drive axles, transfer cases, gearboxes and power take-offs. Such oils reduce friction losses and reduce wear of parts in transmission units, cool and protect rubbing parts from corrosion.
Gear oil is intended:
- to reduce frictional energy consumption,
- to protect parts from wear and tear,
- to reduce vibration, shock loads and noise,
- to remove wear products from the friction zone.
Gear oils must have excellent viscosity-temperature characteristics. They fill hydraulic system lubricates mechanical and hydraulic transmission units industrial machines and gearboxes with gear and worm gears.
The viscosity of the oil is selected depending on the operating conditions:
- maximum - to prevent losses through sealing parts,
- minimum - to start transmission units at low temperatures and reduce friction losses.
When using quality gear oil with good performance Significant savings in fuel and lubricants are noticeable.
Types and differences of tolerances GL4 and GL5
Gear oils are divided into 5 main classes. GL4, GL5 belong to a new class, which appeared thanks to the hypoid gearbox combined in one housing. This design was required so that two incompatible oils could not mix with each other. For her, a class of oils was developed that meets the requirements for different classes.
A new universal class of lubricants is used simultaneously in drive gears and gearboxes:
- With GL5 oils, hypoid gear operation becomes especially reliable when high voltage and shock loads.
- GL4 oils are designed primarily for use in front-wheel drive gearboxes. This type contains half the sulfur-phosphorus additives that create a protective coating on rubbing parts.
The GL4/5 marking is used by Asian manufacturers, the GL4+ designation is used on European-made materials. Some motorists consider these oils to belong to different classes, but they are mistaken.
Gear oil 75w90: synthetics and semi-synthetics
The basic modification of a semi-synthetic product contains 78-45% mineral, 20-40% synthetic and 2-15% additives. The basis of synthetic gear oils is only a synthetic base.
synthetic oil 75W90 is made from polyalphaolefins with appropriate additives or from a hydrocracking agent with additives. The main characteristics of oil type 75W90 are:
- protection of transmission units from friction, oxidation and wear,
- transmission performance improvement,
- the ability to operate in conditions of very low and high temperatures,
- dissolution of salt deposits,
- preservation of polymer seals.
75W90 oil is synthetic, despite the fact that many sellers present it as semi-synthetic.
Overview and characteristics of popular gear oils
Consider the most popular gear oils from various manufacturers.
A series of oils TM-5 from Lukoil with improved viscosity-temperature characteristics was developed for mechanical transmission units with any type gears. This oil is widely used in automotive transfer boxes, drive axles, steering gears, etc. Lubrication allows the operation of transmission units at low temperatures and significantly saves fuel.
Castrol
Synthetic oil 75W-90 from Castrol protects against wear of the part under extreme loads. Recommended for use in manual gearboxes that use VW 501 50 and API GL4 oils.
Zic
Gear lubricant latest generation manufactured by Zic has excellent low temperature fluidity and excellent antifriction properties. The oil will significantly extend the life of the transmission, since it has a full range of additives and can be used in any, even extreme conditions, in manual transmissions and in drive axles. The gearbox is much quieter, and its resource is significantly increased.
Liqui Moly
Synthetic oil "Liquid Moli" (LIQUI MOLY) showed excellent operational properties when working in mechanical gearboxes, as well as in hypoid gears where lubrication is used API class GL4+. Due to its excellent viscosity-temperature characteristics, the oil effectively protects against corrosion and wear with an extended service life.
TNK
TNK semi-synthetic gear oil belongs to upper class and applies all year round. It is manufactured using modern technologies from high quality base oils with the addition of imported components.
Shell
Shell synthetic oils have highest performance and are designed for use in highly loaded transmissions of sports cars.
What are GL 5 oils? This gear lubricants which are very popular in Russia. In many front-wheel drive cars, the transmission is connected to the main gear. It is necessary to pour high-quality gear oil into the gearbox, otherwise the operation of the vehicle will be difficult.
Gearboxes contain gears shaped like a cylinder. The chance of scoring is quite low. Automatic transmission oil should have a low viscosity index. It is known worldwide as ATF. In cars and trucks equipped with mechanical boxes, you need to pour ordinary gear oil.
How to choose a lubricant for transmission
Today, both synthetic and mineral gear oil can be poured into the gearbox. Synthetics affect the gears of the unit in the same way as mineral water. The latter is much cheaper. The choice of oil for the box must be made, taking into account:
- load on the unit;
- speed for relative slip.
The differences between gear oils are in the viscosity index, the concentration of additive elements. Anti-seize additives are composed of sulphurous components. With intensive operation of the gearbox, they modify the surface of metal parts. They form the thinnest film that protects parts from wear.
Currently, GL transmission oils (four and five) are poured into cars. This marking of oils corresponds to API classifications, which is foreign. The fourth API GL is optimally suited for pouring into Russian VAZs. For others domestic cars need to apply another API oil GL (five). In addition, today you can buy universal oil GL4/5.
The driver has the opportunity to easily find out which oil is best suited for his car. To do this, you need to look in the catalog or the operating manual. Many inexperienced motorists believe that GL5 is a better car oil when compared to GL-4. Is it true?
Comparison of these lubricants is incorrect, because they are intended for different machines. If you pour "GL-5" into the VAZ 2109 transmission, the car synchronizers will break. The best car oil for this machine - "GL-4". Failure to follow the manufacturer's recommendations may result in vehicle damage.
Both lubricants are different. good quality. However, it is impossible to use these oil products for other purposes. You don't want to overhaul your car, do you? If in doubt about your own choice, consult with a car service employee.
Subcategories "GL-5"
Auto oil "GL-5" is divided into three subcategories (according to SAE):
After choosing the best operational features the product needs to solve an equally significant problem. It is required to choose a lubricant that has an optimal viscosity index. For example, motor oils corresponding to SAE class 140 can only be used in hot climatic conditions. Lubricants are more suitable for RF SAE class 90. The best option– use universal consumables. Synthetic oil 75w90 will provide high-quality lubrication transmission spare parts even in low temperature conditions.
The difference between "GL-4" and "GL-5"
What is the difference between the fourth and fifth GL? The difference between them lies in the fact that "GL-4" contains only four percent of anti-seize additives, consisting of sulfur and phosphorus elements. GL-5 includes six and a half percent of additive components. In view of this, lubricants have differences in purpose. The fifth GL, also called hypoid car oil, must be poured into highly loaded gearboxes. This oil is best suited for hypoid gears. This is the main difference.
The most competent approach is to use lubricants recommended by the automaker. If the manufacturer of the car wrote in the manual that you need to pour into the transmission hypoid oil, means, buy GL-5. Filling with oil other than hypoid can lead to a variety of problems. So close to overhaul.
Buy consumables only from authorized sellers. Otherwise, you risk running into a fake. It is unable to provide sufficient wear protection for transmission parts.
