GL5 gear oil is a great choice for highly loaded hypoid differentials and yellow metal safe. It is also lower in sulphur and has less extreme pressure (EP) additives. Nevertheless, you should read the MSDS or SDS before you use it.
GL5 gear oil is yellow metal safe
GL5 gear oil is a popular choice for manual transmissions, but it isn’t actually safe for yellow metals. The additives in this type of lubricant can damage yellow metals. Additionally, it can cause problems with brass synchronizers, which depend on friction to speed or slow gears. Moly oil is also not yellow metal safe, and it can cause shifting problems. The good news is that there are many good choices. These include the Amsoil Synthetic Manual Transmission oil and the Redline MT90.
Yellow metals are copper, bronze, and brass. The additive sulfur can corrode these metals. However, GL5 gear oil is safe for these yellow metals. While some forums recommend GL5 gear oil for yellow metals, others state that it isn’t. Copper and bronze are not safe to use with GL5 oil.
Another concern with GL5 gear oil is its ability to wear down the coating of brass synchronizers. Some additives in GL5 gear oils will attach themselves to these synchronizers and form a hard coating. Over time, this coating will wear off and cause your gears to break down more quickly.
The two main gear oils are GL5 and GL4. GL5 is a bit more expensive than GL4, but it has higher levels of EP additives. It can also be used in GL3 gearboxes. It is also suitable for high-offset hypoid gears.
GL5 gear oil is yellow metal safe, but it’s not safe for gears that are made of brass. It will erode the protective black coating on brass. The metal will then be exposed to more friction and wear. In addition, synthetic gear oil will increase the wear of steel gears. Some people prefer to protect their gears with GL5 gear oil.
GL5 has less extreme pressure (EP) additives
The differences between GL-5 and GL4 gear oils are usually primarily related to extreme pressure (EP) wear additives. GL5 is less corrosive and is compatible with a larger range of equipment, such as transaxles. It is also more effective in applications where friction is an issue, such as manual transmissions.
While GL4 and GL5 gear oils are similar in performance, GL-5 has more extreme pressure (EP) additives and GL4 has less. These additives are essential in protecting gears under extreme conditions, and GL5 has twice as much of them. It is often recommended for spur and helical gears in manual transmissions and transaxles, and hypoid gears in automotive axles.
EP additives with sulfur can cause damage to yellow metals. These metals are more easily damaged by extreme pressure. When exposed to high temperatures, sulfur reacts with copper to form copper sulfide, a crystalline form of copper. During extreme pressure, this crystalline form of copper can damage softer machine surfaces.
Automotive gear lubricants should meet OEM requirements. GL5 lubricants usually have a sulphur-phosphorus extreme pressure additive. These additives are important for protecting the face of the gear in high-pressure environments. However, it is worth pointing out that extreme pressure additives can cause damage to copper alloy and other yellow metals.
API GL-5 is formulated for heavy-duty applications, and is suitable for applications where extreme pressure is a problem. These applications include differentials in on-road and off-road trucks, Caterpillar scrapers, and manual-shift transmissions. While GL-5 has less extreme pressure (EP) additives than GL-6, it meets the highest requirements and is used by some manual transmissions.
GL5 is suitable for highly loaded hypoid differentials
GL5 gear oil is a very high-performance gear oil with enhanced anti-wear and anti-seize properties. It is ideal for hypoid gears in automotive axles. GL5 gear oil has a higher EP than GL4 and can be used as a replacement for GL4. It is suitable for limited-slip differentials and high-pinion offset hypoid gears. It is a military grade oil with the following features:
GL5 oil is not backward compatible in synchro-mesh transmissions. Its lower coefficient of friction and increased concentration of EP additives make it less effective at engaging synchros compared to GL-4. The reason for this is that it was specifically developed for hypoid gear designs, and most gearboxes use hypoid gear designs. Therefore, hypoid gear oil must contain specialized additives for extreme pressure.
GL5 is designed to protect hypoid gears under extreme pressure. It is compatible with hypoid gears of high offset and severe service. In addition, it has excellent anti-wear and anti-shock properties. While GL4 is ideal for light loads, GL5 is a more versatile choice for heavily loaded hypoid differentials.
GL5 is suitable for highly loaded hypoisd differentials and axles. It contains an extreme pressure additive to create a buffer between mating metal surfaces and reduce wear and tear on these components. GL5 also meets the API GL-5 specification, which makes it an excellent choice for axles with Hypoid Gears. The API GL-5 specification also allows for the mixing of GL5 with other oils.
GL5 is a fully synthetic gear oil with a high SAE viscosity level. It is particularly suitable for highly loaded hypoid differential gears and drive axles, multi-disc brakes, and bevel and spur gears. Furthermore, GL5 is designed to limit slip and meet the highest power requirements.
GL3 and GL4 gear oils are designed for medium and heavy-duty applications. They are suitable for manual gearboxes and transaxles, and have a light-moderate level of extreme pressure additives. The GL3 and GL4 oils can be used in the same systems. These oils do not require flushing, which is an important consideration.
GL5 has lower sulphur content
You should be able to tell if an oil is GL5 by its GL-number. GL5 has lower sulphur content than GL4, but it doesn’t necessarily mean that it is better. The GL number is a standard identifier for gear oil. The higher the number, the more EP additive it contains. Historically, EP additives contained sulphur, and this caused a bad smell, particularly in high-temperature engines. GL-5 is also more severe in corrosion protection, and should only be used in transmissions that are backward compatible.
GL5 gear oil has high-performance anti-seize and anti-wear functions that are particularly useful in high-speed hypoid gears. It also contains anti-wear and anti-seize additives that are aggressive towards non-ferrous metals. However, if you’re buying gear oil for a car, you may want to stick with a standard GL oil. GL4 gear oil is good for medium-speed and low-load operation. It is suitable for manual and transaxle applications and has lower sulphur levels.
GL5 is generally thinner than GL4, and the weight code indicates how thick it is in different conditions. For example, 80W-9 is thicker in cold temperatures than 90W-9 oil. GL5 is the recommended oil for high-speed hypoid gears in automobiles, but GL4 is a better choice in some cases.
While GL4 is the preferred choice for most people, GL5 has lower sulphur contents. Moreover, GL5 contains less copper than GL4, making it ideal for engines in hot climates. It is also cheaper than GL4, and a good synthetic will help you save on expenses by reducing your fuel bills.
GL5 gear oil is also better suited for automotive axles, as it has a higher pressure rating and is ideal for high-speed, high-load applications. The GL5 gear oil can also be used for limited-slip differentials and high pinion offset hypoid gears.