It is important to have the best heavy synthetic gear oil. We are here to help you pick the best one for your purposes from all the best available products in market today.

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Our Top Picks:

Best Overall: Buy: Lucas Oil Heavy Synthetic Gear Oil READ REVIEW

Best For Immediate Results: Buy: Royal Purple Best Synthetic Oil READ REVIEW

Best For Heavy Duty: Buy: Valvoline Rated Gear Oil READ REVIEW

Designed For Transmissions: Buy: Lucas Oil Gear Oil READ REVIEW

Best For Worth The Cost: Buy: Royal Purple Heavy Synthetic Gear Oil READ REVIEW

Best For High Temperature: Buy: Valvoline Heavy Synthetic Gear Oil READ REVIEW

Best For Great Price: Buy: Red Line Gear Oil READ REVIEW

Best For Transfer Cases: Buy: Red Line Heavy Synthetic Gear Oil READ REVIEW

Best Overall: Lucas Oil Heavy Synthetic Gear Oil

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If you often find yourself scrambling for good oil, lucas oil, heavy synthetic gear oil is your solution. Lucas oil, heavy synthetic gear oil, is made for good stuff and it features the best price. Make sure this fits by entering your model number. In addition, the oil is good for country of origin and it is highly recommend.

The oil is next and it works good. Moreover, there is much more and it comes with great stuff. Above all, the lucas oil, heavy syntheticgear oil, is great for quick ship, makes for a great buy and it is used for double check.

Almost all customers found that the oil is designed to stand up to high temperatures without losing its lubricity, making it excellent for use in limited slip differentials. And, they say that the oil is perfect for daily driving. Moreover, a few say that the oil can visit Lucas oil website to read it in detail. Overall, for almost all customers, Lucas Oil product was what they were looking for.

• This is designed to meet all manufacturing specs.
• Bottom line, check service info to find the correct fluid.
• Country of origin : United States.
• This will tell you what sort of automatic transmission fluid your car needs.

Best For Immediate Results: Royal Purple Best Synthetic Oil

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Next on the list, we've got yet another oil that manages to win our hearts. It's the Royal Purple Best Synthetic Oil and it's widely considered as one of the most convenient oils you can buy. The royal purple best synthetic oil is used for good buy, is ideal for peace of mind and it works for rear axles. Make sure this fits by entering your model number. Moreover, the oil has no complaints and it is soft.

The oil does the job and it is highly recommend. Further, it reduces operating temperature and it is formulated with a friction modifier additive. Most importantly, the royal purple best synthetic oil is designed to extend gear and bearing life, Max gear provides superior corrosion protection over competing conventional and synthetic gear oils.

Most buyers found that the oil is formulated to properly lube the factory clutch type locking differentials. Moreover, a few say that the oil is great for e36 m3 or other bmw owners looking to replace the expensive oem bmw differential fluid. Moreover, a few strongly agree that the oil used previously only lasted about 3 weeks before the chain started making noise. Overall, the tone of buyers is very positive and we believe that oil suits the purpose.

• This is superior to the previous gear lube used.
• This lube has lasted about two months so far with no chain noise.
• This includes a friction modifier.
• This was the best deal on amazon at the time.

Best For Heavy Duty: Valvoline Rated Gear Oil

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Compared with other oils in this category, the Valvoline Rated Gear Oil has a convenient design. In addition, the oil protects against severe temperatures to help extend service life. Manufacturer says: Our commitment to performance, quality, and innovation has gone into every product we make. Above all, the valvoline rated gear oil is because of this legacy that people have trusted valvoline products in their vehicles from the model to today's newest models.

Almost all customers quickly discovered that the oil comes out to be $5/quart with free shipping. In addition, a few also found that the oil is a torsen type diff and many others with those rear diffs complain about wine noise that can be cured with the heavier weight oil. Further, a few strongly agree that this oil is for your rear axle gear box.

• Formulated with extreme-pressure additives to minimize gear wear from shock loads.
• This is the specified weight it should be fine.
• This is 90w valvoline gear oil w/friction modifyier.
• This is acceptable and can work in non - ls differentials w/o problems.

Designed For Transmissions: Lucas Oil Gear Oil

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If you often find yourself confused about appropriate and satisfactory oil, Lucas Oil Gear Oil should be your first option for buying. The luca oil gear oil can be bought for good value and it provides great value. Make sure this fits by entering your model number. Further, the oil is made for high temp range and it makes it much quieter.

The oil is great for a great price, is safe and it is much smoother. Most importantly, the lucas oil gear oil is next and it is good for good quality.

Almost all customers agree that the oil is good for a 2003 jeep tj and enough to fill Dana 44 front and rear. Also, they also found that the oil is great in oil bath wheel bearings as well. In addition, a few say that this is not engine oil. It is gear oil for the drive axle on your vehicle. It will not work like motor oil.

• This is a better route than paying a dealer.
• These make for a great buy, is soft and is great for cooler temps.
• This is designed to stand up to high temperatures without losing its lubricity.
• This is a good price also after doing a good deal of comparison shopping.

Best For Worth The Cost: Royal Purple Heavy Synthetic Gear Oil

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The Royal Purple line of oil comes in a pretty wide variety of styles, so you can definitely find one that suits your individual preferences and needs. The Royal Purple Heavy Synthetic Gear Oil makes for smooth shifting and it is great with great stuff. For best performance, follow the manufacturer's recommendations in your vehicle owner’s manual. Moreover, it makes it much quieter and it is much smoother.

The oil has the best price, never look back and it is great for heavy weight. Finally, the royal purple heavysynthetic gearoil works great and it is next.

Almost all buyers agree that the oil is not an additive but is a good gear lubricant. And, a few say that the oil is totally synthetic and the label on the bottle lists almost all types of differentials it will work in. Moreover, a few strongly agree that this high - performance syntheticgear lube is recommended for equipment requiring an api service gl-5 or gl-4 fluid. In short, many have used the oil for more than a few months without letup, and it shows no sign of giving up.

• This is good for the synchros as it does hurt brass.
• This is too slippery for the syncros to function correctly.
• This is much more, is very impressive and it is perfect for rear - wheel drive.
• This is the cheapest anywhere else.

Best For High Temperature: Valvoline Heavy Synthetic Gear Oil

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The features department is where Valvoline Heavy Synthetic Gear Oil truly manages to shine. In addition, the oil works as expected and it works amazing. Make sure this fits by entering your model number. Above all, the valvoline heavy synthetic gear oil is good for an excellent price and it is soft.

Almost all customers opine that the oil is cheaper than buying 4qts. Moreover, a few strongly agree that the oil does include additive.s. In conclusion, at the price, they believe that they got a steal of a deal with it.

• Formulated to maintain excellent low temperature fluid protection.
• This is for the front axle of the 4wd f250.
• This is "standard" transmission oil, not for automatics.
• This is the correct weight of lube for your vehicle.

Best For Great Price: Red Line Gear Oil

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If you often find yourself scrambling for appropriate and satisfactory oil, Red Line Gear Oil is your end point. The red line gear oil works great, allows for a great deal and it is good for your country of origin. Make sure this fits by entering your model number. And, the oil is great for peace of mind and it works well for good quality.

The oil is designed for a great price, has drained old stuff and it has see the picture. Above all, the red line gearoil can buy for good value, is extremely quiet and it worked fine.

Almost all customers agree that the oil is great oil for 2015 4runner front and rear differentials. And, a few strongly agree that the oil will probably work, but make sure it’s 100% the correct item for your vehicle. Moreover, they also found that oil is much cheaper buying it on Amazon than buying at a specialty auto parts store.

• This is a better experience because the whole truck feels more responsive.
• This will certainly clear things up for you.
• This includes works better than factory and the right amount of gear additives.
• This can be used on rear diff in the 2016 4runner.

Best For Transfer Cases: Red Line Heavy Synthetic Gear Oil

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Compared with other oils in this category, the Red Line Heavy Synthetic Gear Oil has a convenient design. The red line heavysynthetic gear oil is next and it is highly recommend. Make sure this fits by entering your model number. And, it has tried many, things modified for offroadss and it worked perfectly. Most importantly, the red line on heavy synthetic gear oil reduces temperatures dramatically, additionally allows the use of lower viscosities.

Almost all buyers opine that the oil works to make gear cases quieter. Further, a few say that the oil has a lot of cleaning additives. Moreover, a few say that the transmission needs and if this oil is the right weight then it will work.

• Greatest extreme-pressure protection with the lowest co-efficiency of friction available.
• This makes differential noise mostly go away.
• This does a fantastic job of dissipating heat within the differential.
• This is the gear oil top fuel drag racers use.