Best 75w140 Synthetic Gear Oil

Are you wondering which the best 75w140 synthetic gear oil is? Well, that is why I have decided to put this piece together. But, I must also confess that it is not easy to select the best synthetic 75w140 gear oil because as it were, the market is flooded with several brands. Nonetheless, I assure you that before you hit the last paragraph of this review, you’d have found the best 75w140 gear oil.

However, before I talk about the top products I have sampled for you, it is imperative we learn about something.

Why Use Synthetic Gear Oil?

If you have a big vehicle, it is important to know why you should insist on using synthetic oil. The main reason why you should choose this type of oil than others such as mineral oils is synthetic gear oil performs quite well than any other oil.

Synthetic gear oil is particularly good under extremely cold or hot conditions. With that in mind, let’s now look at the products that carry the day. Therefore, you need synthetic gear oil for these three main reasons:

  • Cooling the gear and engine in general.
  • Protecting the gear system from unnecessary rust.
  • Lubricate and guard the car gear from wear.

8 Best 75w140 Synthetic Gear Oils Reviews

This list contains the best 75w140 synthetic gear oil that many users have found to give remarkable results:

1. Valvoline SynPower SAE 75W-140 Full Synthetic Gear Oil 1 QT

This gear oil is specially formulated to give your vehicle complete and long time gear protection. As such, the formulation helps maintain low-temperature especially inside the fluid tank. In addition, the gear oil gives your vehicle exceptional thermal stability in terms of cleanliness and longevity.

Valvoline SynPower SAE 75W-140 Full Synthetic Gear Oil 1 QT is also filled with special additives that enable the reduction of chattering, which is a norm in most limited slip differentials.

Besides, this best 75w140 gear oil is excellent in the protection of your vehicle’s gear teeth from corrosion and rust thus assisting in the durability of the gear.

Key Features

  • Filled with additives.
  • Works for limited and conventional differentials.
  • Item weighs 1.9 pounds.


  • Helps increase gear life.
  • Maintains low temperatures.
  • Ideal for thermal stability.
  • Reduces chattering.
  • Good for limited and conventional differentials.


  • You need to use it regularly for good results.

2. Lucas 10122 75/140 Synthetic Gear Oil – 1 Gallon

This gigantic 75w140 synthetic gear oil will solve all your vehicle gear problems. The product weighs a massive 7.6 pounds and is characterized for its long-lasting lubrication effects on your vehicle gear.

Thanks to some of the special additives, Lucas Synthetic Gear Oil reduces gear noise significantly. In addition, the additives help especially in areas inside your vehicle gearbox that are always on the run by increasing lubricity.

This 75w140 gear oil does an excellent job especially in limited differentials. The other great thing about this gear oil is that it has been designed to work in extreme conditions such as extreme heat or excessive cold without losing the lubricity that it came with.

Key Features

  • Vehicle specific.
  • 75w/140 synthetic oil.
  • Made in China.
  • The package weighs 7.6 pounds.


  • Best for heavy-duty vehicles.
  • Lubricates the entire gear system for long.
  • Increase lubricity.
  • Good for limited differentials.
  • Doesn’t lose manufacturer lubricity.


  • Heavy.
  • The oil is vehicle specific.

3. ROYAL PURPLE MAX Gear 75w140 Quart Bottle Oil

True to its name, ROYAL PURPLE MAX Gear 75w140 Quart Bottle Oil comes in a royal purple container. With staggering 945ml best 75w140 synthetic gear oil, you bare sure that your vehicle’s gear is taken care of.

Although you can use this product as you wish, experienced mechanics recommend that you strictly use it on the front and the rear limited differentials. You can also use this synthetic oil in marine engines especially the lower gear section as well as in various trucks and automotives’ manual transmissions.

The ultra-tough oil has been specially engineered to do a spectacular job on heavy-commercial vehicles especially those that are loaded to the brim or are constantly on the road.

Key Features

  • Packaged in a 945-ml royal purple plastic container.
  • Filled with friction modifier and other essential additives.


  • Maximizes  vehicle horsepower.
  • Weighs 2 pounds.
  • Reduces temperature.
  • Protects gear teeth against corrosion.
  • Responsible to the environment.
  • Extends bearing and gear life.


  • Selective on engine brands.

4. Red Line 57915 75w140 GL-5 Gear Oil – 1 Gallon

If you are a person fascinated by exceptional packaging and attractive colors, then Red Line 57915 75w140 GL-5 Gear Oil – 1 Gallon is the best 75w140 synthetic gear oil you need to order.

Some of the benefits you are likely to witness after using this 3.8-ltr synthetic oil include extreme lubrication in automatic cars, enhanced slipperiness especially in low operating temperatures among others.

In addition, this gear oil 75w140 is nice in reducing oxidation when you compare it with a majority of the gear oils in the market especially those that surpass API GL-5 specifications.

In the end, when you use this best 75w140 synthetic gear oil, you will enjoy better mileage, less gearbox wear, as well as extended drain intervals.

Key Features

  • Packaged in a red plastic container.
  • Item weighs 7 pounds (3.8 liters).
  • Manufactured by Red Line.


  • Extended drain intervals.
  • Limited gear wear.
  • Better mileage.
  • Accepts a variety of car brands.


  • It may go on waste unless you use all of it.

5. Ford Genuine Fluid XY-75w140-QL SAE Synthetic Rear Exile (Pack of 4)

Thanks to the high-end synthetic base and additives, the gear oil will not only provide the needed high-temperature thermal but also the required oxidative temperature. The other good thing you will realize about this product is it aids in the reduction of operating temperatures.

For hypoid gears, this 75w140 synthetic gear oil provides enhanced protection against wear. In addition, this synthetic gear oil provides exceptional gear stability, guards your engine against rust as well as corrosion.

Because the product meets all needed fill for life requirements set by the Ford Motor Company, you will be assured that you are ordering the right product.

Key Features

  • Manufactured by Ford Motor Company.
  • Item weighs 7.7 pounds.
  • Comes in a pack of 1 or 4.


  • Improves thermal temperature.
  • Provides exceptional shear stability.
  • Stabilizes oxidation.
  • Reduces operative temperature.
  • Protects gears against wear and tear.
  • Reduced corrosion.


  • Does not need you to mix with any oil.

6. Lucas Oil 10121 Synthetic SAE 75w-140 Gear Oil (32 Ounces)

With a premium viscosity of 75W140, this one-gallon synthetic gear oil is all you need to lubricate your gear teeth. You will love its super slick material, non-foaming, and it’s long lasting.

Besides, this product will provide the needed lubrication. The other thing you will love about this gear oil 75w140 comes with additive package, which cushions gears as well as squeezes pressure under extreme conditions.

It is also important to mention that this synthetic gear oil has the unique ability of providing excellent results without ever losing its imbedded lubricity. Finally, Lucas 32-Ounce Oil 10121 Synthetic SAE 75w-140 Gear Oil is excellent when dealing with limited slip differentials.

Key Features

  • Ideal for limited differentials.
  • Manufactured by Lucas Oil.
  • Meant for heavy-duty vehicles.
  • Volume: 1 gallons.
  • Weighs 1.99 pounds.


  • Superior slickness.
  • Resists higher temperatures.
  • Less gear noise.
  • Easy to blend with other gear brands.


  • Sometimes the volume is less than the labeled amount.

7. Mobil 1-Quart 1 102490 75w-140 Synthetic Gear Lube

Mobil 1-Quart 75w140 Synthetic Gear Oil is made in the United States of America and meets all the necessary requirements for gear oil. The package weighs 1.7 pounds, with a gear oil volume that will give you a service of several days.

What is more, this product does better in a 10.5 sterling Ford axel. Additionally, you will not need to add any slip additive for better performance. Those that have used this product say that it does an exemplary job on cold temperatures that to its viscosity.

The product is reinforced with friction modifier making it the perfect synthetic gear oil for limited differentials, axel as well as gears. Besides, the size and shape of the bottle makes it extremely easy to refill.

Key Features

  • Filled with friction modifier.
  • Packaged in a plastic bottle.
  • Manufactured in the U.S.


  • Quality product for longevity.
  • Easy to refill.
  • Makes gear shifting smooth.
  • Best in cold and hot temperatures.
  • No additional additives needed.


  • Might need more of it for exceptional results.

8. Liqui Moly 1-Ltr 20042 Limited Slip Synthetic Gear Oil

This 1-ltr synthetic gear oil from Liqui Moly is made in Germany. It is designed to give highly stressed axles a break. The manufacturer says this gear oil is especially good for high-velocity cars such as those that take part in the rally.

You can also use this product on BMW and other luxurious cars thus giving you smooth gear shifting because of the oil’s exceptional lubricity.

Although with a capacity of 1 liter, you will be sure that the oil will lubricate your car gears for long. Besides, the oil is excellent in reducing gear teeth corrosion.

Key Features

  • Packaged in a plastic container.
  • Weighs 8.5 ounces.
  • Filled with additives.
  • Made in Germany.


  • Reduces gear teeth corrosion.
  • Enhances smooth gear shifting.
  • Reduces gear noise.
  • Lubricates the gear teeth.
  • Good for sports, luxury cars and heavy-duty vehicles.
  • Easy to drain.


  • Choosy with brands.
  • Does not reduce noise in some car brands.

Best 75w140 Synthetic Gear Oil Buying Guide

Before deciding which 75w140 synthetic gear oil is best for your truck, luxury, or sport car, you need to consider a few important things. I’ll cover a few yet important things you should look into before you press that ‘Order’ or ‘Add to Cart’ button.

Vehicle Type/Car Brand

The first consideration is the type of vehicle you want to use the synthetic gear oil. Perhaps you’ve seen throughout this review that these products are suitable for trucks, heavy-duty vehicles, luxury cars because many have bigger engines and as such heavy consumers, and sports cars.

The reason you should be keen on the type of car is it could be useless to buy a 75w140 gear oil, which many a times goes double the price or more than regular gear oils yet it doesn’t change a thing.


While it is not a big deal, nobody would want to spend their money on gear oil that is stuck inside a container that would be a problem to empty its contents. That’d be absurd. Sometimes, you may be in a hurry thus you need a container that drains up everything within seconds and you are gone.


This is very important. The best 75w140 synthetic gear oil must come with additives. Thanks to the additives, you are able to enjoy all the benefits that come with using or changing from 80/90W gear oils to 75W 140 types of gear oils.

Yes, synthetic gear oil 75w140 performs better in hot and cold temperatures.

Frequently Asked Questions (FAQs) The Best 75w140 Synthetic Gear Oil

Q: Which types of vehicles use 75w140 gear oil?

A: Pickup trucks, semi trucks, large cars, sports cars, SUVs, tractors and some boats use 75w140 gear oil.

Q: How much gear oil does an average car need?

A: An average pickup truck is likely to require 2 or 3 quarts of synthetic gear oil each time you will change it.

Q: Is 75w140 better than 75w90?

A: 75w140 is heavier thus ideal for a severe service. It is the best for rear diff on heavy-towing or vehicles are constant and speedy run.

Q: Which gear oil is thicker between 75w140 and 75w90?

A: At operating temperature, 75w140 is thicker than 75w140. However, they have almost the same viscosity at room temperature.

Final Thoughts

Hitherto to, I’m sure you’ve been well-informed about the best 75w140 synthetic gear oil. Remember that before you purchase any of the products mentioned herein, check the condition of your vehicle’s gearbox to ascertain its condition. Once you find it needs lubrication, then you know what to do.