Best 75w 140 Synthetic Gear Oil

The right gear oil can make the difference between a smooth ride and a noisy, jerky one. You may have noticed before that some synthetic gear oils are better than others in terms of quality. However, not all synthetic gear oils are created equally – there is a huge price range.

There’s a lot of synthetic gear oil on the market. Which one is best for your money? We’ve compiled a list of the 7 best 75w140 synthetic gear oils that will help keep your car running smoothly and efficiently.

List of the best 75w140 Synthetic Gear Oil

#1 Red Line 57915 75W140 GL-5 Gear Oil – 1 Gallon

The Red Line 57915 75W140 GL-5 Gear Oil – 1 Gallon has been formulated as a high performance gear oil for both on and off road applications where additional protection against wear is desired.

It offers excellent lubrication under extreme conditions due to its fully synthetic formula which contains polyester base stocks that are resistant to oxidation and thermal breakdowns at higher temperatures than petroleum oils can withstand without breaking down. 

Red Line 75W-140 GL-5 Gear Oil – 1 Gallon is a premium quality, high performance gear lubricant designed for use in all types of automotive and industrial differentials. Red Line 75W-140 GL-5 Gear Oil – 1 Gallon contains additional friction modifiers to make it suitable for most clutch-type limited slip differentials.

This synthetic oil is a favorite of mechanics and car enthusiasts alike. It’s great for those who are looking to extend the life of their transmission, especially if they’re into off-roading or frequent driving on dirt roads.

The best gear oil is Red Line 57915 75W140. It’s used by professional mechanics for a reason: it does its job well and lasts long. This oil contains no friction modifiers and is recommended for use in API GL-5, and SAE J2360 gear oils.

#2 Ford Genuine Fluid XY-75W140-QL SAE 75W-140 

When it comes to rear axle lubricant, you want the best. The Ford Genuine Fluid XY-75W140-QL SAE 75W-140 Synthetic Rear Axle Lubricant is a synthetic lubricant formulated for enhanced wear protection and long life with reduced operating temperatures and less oil consumption when compared to conventional products. It’s truly something worth bragging about!

The XY-75W140-QL is a synthetic base oil that resists oxidation and thermal breakdowns, which are two common causes of wear in the rear axle. This means that you can expect a long life from these products, with less frequent drain intervals. 

Ford has been producing cars for decades, so they know what customers want. This oil is recommended by the Ford Motor Company and it’s easy to see why – this oil will keep your transmission running smoothly no matter how rough you are on it.

The XY-75W140-QL is the perfect solution for those looking to reduce their operational costs with its excellent shear stability and corrosion prevention. The product can decrease your operating temperature, which reduces fuel and oil consumption by up to 20%. Plus, it also provides extra protection on hypiod gears!

This synthetic gear oil is also formulated to resist the effects of high operating temperatures, which can lead to oil consumption. Lower oil consumption means less overall waste and lower vehicle emissions when paired with a corresponding Ford Genuine Fluid compatible filter. These properties, along with an extended drain interval of up to 150K miles (241,401 km), make this oil a top choice.

#3 Valvoline SynPower SAE 75W-140 Full Synthetic Gear Oil 1 Q

Valvoline SynPower SAE 75W-140 Full Synthetic Gear Oil provides outstanding wear protection and lower compartment operating temperatures. It includes multigrade oils that are engineered to provide superior lubrication at start-up and high temperatures, thereby ensuring maximum protection.

It helps provide excellent low temperature fluid protection and contains special additives to reduce chattering in limited-slip differentials, corrosion and gear teeth rust. Recommend for conventional and non-synchronized manual transmissions and limited slip differentials where API GL-5 or API GL-4 fluid is specified.

This gear oil can help your car last longer. If you have a mileage over 10,000 miles the Valvoline SynPower SAE 75W-140 Full Synthetic Gear Oil is perfect for you! The synthetic oil will keep your engine oil at the proper level, reducing friction and allowing your vehicle to run smoothly.

For added protection, it includes a rust and corrosion inhibitor, a seal conditioner that improves oil film strength between sliding surfaces. It has a viscosity index rating of 140 (SAE 10W-30 = 100) making it compatible with most conventional automatic transmission fluids as well as limited slip differential fluids.

SynPower SAE 75W-140 Full Synthetic Gear Oil 1 QT is formulated to provide a longer service life and outstanding thermal stability. It also includes rust and corrosion prevention to keep your car in good shape.


The Royal Purple Max-Gear 75W140 Max Gear 75W140 is a high performance gear lubricant that provides maximum protection for all types of gears. Max Gear is preferred because it does not require using any additional additives.This product reduces drag in the drive train, resulting in increased fuel economy and less noise.

The Royal Purple Max-Gear 75W140 is the ultimate extreme pressure synthetic lubricant. Max-Gear combines Synerlec additive technology with synthetic oils to form a superior lubricant that offers improved protection and performance over conventional full-synthetic and mineral oil based product

Max Gear is the perfect gear lube for 4WD vehicles, ATV’s and UTV’s. It has excellent cold weather properties and is formulated to provide superior protection from rust and corrosion. Max Gear provides a long service life with less maintenance required over other brands of gear oils.

#5 Amsoil Severe Gear SAE 75W140

Fifth on our list is the Amsoil Severe Gear SAE 75W140. The Amsoil Severe Gear SAE 75W130 is an advanced, extreme-pressure (EP) gear oil formulated with the latest synthetic technology to provide long-lasting protection against metal-to-metal contact. This proprietary AMSOIL formulation features a unique combination of highly refined base oils and advanced additive technology that create a superior iron-sulfide barrier coating on gear surfaces, providing the ultimate line of defense against wear, pitting and scoring.

This synthetic gear oil contains premium quality, heavy-duty, multi-purpose gear lubricant designed for use in automotive and truck transmissions and differentials. It provides outstanding performance under the most severe conditions of temperature, load and contamination.

This synthetic gear oil provides outstanding performance in differentials, transmissions and rear axles. This product is formulated with a high viscosity index for prolonged fluid life, excellent cold-flow properties for winter usage. It has exceptional thermal stability under heavy loads to protect gears from wear caused by heat buildup.

#6 Mobil 1 102490 75W-140 Synthetic Gear Lube – 1 Quart

 Mobil 1 102490 75W-140 Synthetic Gear Lube  is a premium, high performance gear oil formulated with advanced synthetic technology. Mobil 1 Synthetic Gear Lube has been engineered to provide maximum protection for both manual and automatic transmissions under all driving conditions.

The Mobil 1 Synthetic Gear Lube is recommended for use where API GL-5 rated oils are specified including: light duty trucks, SUVs, vans, RVs, motorcycles, ATV’s. It also maintains viscosity under a wide range of operating temperatures to help maximize the life of engines.

Mobil 1 Synthetic Gear Lube has been engineered to deliver improved wear protection and increased torque capacity over conventional petroleum-based lubricants. This product can help reduce the risk of component failure due to wear and tear, while also reducing noise levels in vehicles that have limited slip differentials.

#7 Lucas 10122 75/140 Synthetic Gear Oil – 1 Gallon

The Lucas 10122 75/140 Synthetic Gear Oil is a premium quality, multi-purpose gear lubricant that provides excellent protection for both manual and automatic transmissions. It is fortified with special additives to provide extra film strength and wear resistance in high temperature applications such as limited slip differentials. This product also contains rust and oxidation inhibitors to protect gears from corrosion.

This synthetic gear oil offers superior performance in high load, severe duty and high speed applications.It’s formulated with a special additive package for better lubricity, which reduces gear noise and also lengthens the life of your bearing.

Lucas 75/140 Synthetic Gear Oil contains no harmful solvents or pour point depressants to ensure consistent viscosity throughout the temperature range of -40°F to +300°F. Which gives it enough protection for your automobile and keeps the gears in your vehicle running smoothly


When looking for the best 75w140 synthetic gear oil, it is important to know what type of engine your vehicle has and which specifications on that engine are necessary.

If you’re not sure what type of engine you have or if there are any specific specs you should be paying attention to, contact a professional before purchasing an oil. Choosing a synthetic gear oil specifically designed for your make/model will save time and money in the long run by preventing repairs from happening as often. 

We hope you found this article useful and informative! If you need help selecting the best gear oil for your car, we’ve compiled a list of 75w140 synthetic oils that are designed to keep your engine running smoothly no matter what condition it is in.

Which one do you use?

Tell us in the comments below.


Which oil is thicker 75W90 or 75W140?

There are many different types of oil but two that you might have heard of are 75W140 and 75W90. It is important to know which one to use in your car because they both have their own special uses and features. Because of its increased weight, the 75W140 is better at preventing wear on the gears and therefore works in a wider range of temperatures.

Gear oils undergo a viscosity index grading to determine which oil is the appropriate thickness for your specific application. For example, if you have an axle that needs 75W90 gear oil then a thicker oil will provide more protection than a thinner one would against shock loads and thermal expansion respectively.

75W90 is a thinner oil that has less viscosity than 75w140. This makes it ideal for applications where there are rapid changes in temperature and the gear oil needs to be able to flow easily so as not to leave any residue on gears. It also works well when using an engine with internal cooling, like many modern engines.

What’s better 75W90 or 75W140?

The answer depends on what you’re trying to get out of your synthetic oil. The 75w90 is a good choice if you have an engine with internal cooling and want to use a thinner gear oil.It’s also good for improving efficiency in cold and hot environments as it will flow without leaving residue on gears.

The 75w140 is thicker than the 75W90 which means it can provide more protection against shock loads and thermal expansion.

When selecting a gear oil for your car, you’re choosing three different variables:

  1. The base oil type
  2. Oil viscosity
  3. Additives

The base oil type indicates the chemical make-up of the gear oil. 75w90 is generally a lighter weight than other types which makes it a good choice for use in an engine with internal cooling and also helps improve efficiency during cold and hot temperature conditions.

When selecting viscosity, you are choosing how thick or thin the oil is. The higher the viscosity, the thicker it will be and as a result, more protection against shock loads or thermal expansion.

When selecting additives for gear oil, there are many types of choices including friction modifiers to reduce heat build-up in gears; antiwear compounds which can help prevent wearing on metal surfaces; rust inhibitors.

What is 75W140 gear oil used for?

75W140 gear oil is made specifically for the cold winter environment to provide thickness and protection while maintaining a comfortable viscosity.

Gear oil is a necessity for almost every modern vehicle, with the exception of newer transmissions. 75w140 gear oil provides an optimum balance between viscosity and ability to handle heat that makes it great for everything from older cars to diesel engines.

If you don’t like oil thinning, the 75w140 gear oil is equipped to last. It’s relatively inexpensive, but offers the protection needed to get through tough terrain.

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