Are you planning to buy gearbox additives, and are you confused about the options ? You have landed on the right page.

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Our Top Picks:

Best Overall: Buy: Prolong Super Lubricants Gearbox Additive READ REVIEW

Best For Power Steering: Buy: Xado Gearbox Additive READ REVIEW

Best With Enough Treatments: Buy: Hapco Products Co Gearbox Additive READ REVIEW

Best For Use: Buy: Slick 50 Gearbox Additive READ REVIEW

Best For High Mileage: Buy: Bars Leaks Gearbox Additive READ REVIEW

Best With Commercially Available Gear Oils: Buy: Liqui Moly Gearbox Additive READ REVIEW

Best For Extreme Conditions: Buy: Motul Gearbox Additive READ REVIEW

Best For Smoother Shifts: Buy: Cerma Gearbox Additive READ REVIEW

Best Overall: Prolong Super Lubricants Gearbox Additive

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Compared with other additives in this category, the Prolong Super Lubricants Gearbox Additive has a design with broader appeal. The prolong super lubricants gearbox additive includes a formula with anti-friction metal treatment technology. Make sure this fits by entering your model number. And, the additive is compatible with Mercon v, allows for high speeds and it added a bottle.

Lastly, the prolong super lubricants gearbox additive has many other lubricants and it is unbeatable.

Most customers quickly discovered that the additive is no hype at all, it is true. In addition, they say that the additive is and is smooth enough to drive every day and not worry about it anymore. Furthermore, a few also found that the additive will last but so far so good.

• This stuff is like a magic transmission treatment.
• This is designed for smoother shifts and it is easy.
• This is another in a great line of products.
• It is hard to shift into first gear from a complete dead stop.

Best For Power Steering: Xado Gearbox Additive

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Best part: Xado Gearbox Additive costs comparatively low and it is available to ship in 24 hours. The xado gearbox additive protects them from extreme heat and protects them from future wear. Make sure this fits by entering your model number. And, it is convenient to use and it is designed for low speeds.

The additive is great with smooth shifts and it makes for a huge difference. Most importantly, the xado gearbox additive is great for transfer cases and it works like a miracle.

Almost all customers quickly discovered that the additive comes out as a paste like substance and not a liquid. In addition, they also found that the additive does not go into an auto trans. And, they say that the ex120 for manual transmission treats manual transmission with fluid capacity of up to 2 quarts.

• This is used to, especially when accelerating onto freeways or for passing.
• This is a really good question actually.
• This is universal for automatic,s works well and it is easy.
• Universal for automatic, cvt, tiptronic, manumatic, semi-automatic transmission.

Best With Enough Treatments: Hapco Products Co Gearbox Additive

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The Hapco Products Co Gearbox Additive's high-end materials makes sure that it ages well with use. The hapco products co gearbox additive is compatible with all conventional and synthetic oils / fluids. Make sure this fits by entering your model number. Also, it is much more, Add a bottle and it makes a huge difference. Above all, the hapco products co gearbox additive can also be added at any time as a seal conditioner to help prevent future leaks.

Almost all customers opine that the additive is sold in local auto stores. Further, they say that the additive is worth every penny and also causes rough idle. And, they say that the fluid reservoir has a long neck not much bigger than the filler cap.

• This has a power steering leak.
• This is leaking from a rubber seal, yes.
• This will stop a leak anywhere there is a gasket.
• Positively stops oil / fluid leaks - guaranteed or your money back!.

Best For Use: Slick 50 Gearbox Additive

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The Slick 50 Gearbox Additive is satisfactory and appropriate and fits well with your daily use. The slick 50 gearbox additive can be added anytime or while doing a transmission fluid change, leaving adequate fill space. Make sure this fits by entering your model number. Also, this is used for loss of torque and it makes it much quieter. Most importantly, the slick 50 gearbox additive provides additional protection to transmissions.

Almost all buyers agree that the additive is designed for use in the latter, not the former. Also, a few also found that the additive is a good thing for transmission. Also, they strongly agree that the additive does not specifically say not to use it in synthetic transmission fluid, it will probably work. To sum up, the tone of buyers is very positive and we believe that the additive suits the purpose.

• It is like gold in a bottle.
• This is used to clunk, shift erratic, and make tons of noise on the road.
• This has a fresh v8 engine, a 318, but the old automatic transmission.
• This will help your transmission but it may not stop the leak.

Best For High Mileage: Bars Leaks Gearbox Additive

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The bars leak gearbox additive's superior materials make sure that it ages well with use. The bars leak gearboxadditive restores older and high - mileage gear performance. Helps with small leaks (if you need to add oil 1x per month), medium leaks (if you need to add oil 1x per week), and other oil related problems. These additives stop and seal gar oil leaks as well as reduce noise.

The additive is for extreme pressure and it is much more. Also, the additive includes tackifying agents and highly sheer-stable multigrade viscosity modifiers to keep oil on the gears and bearings where it can better lubricate, especially at higher temperatures. Above all, the bars leak gearbox additive allows product to flow even at very low temps.

Almost all buyers found that the additive is used for a car or truck. Further, they also found that the additive restores older and higher - mileage gear performance. Moreover, a few say that the fluid starts running out of the hole, it is full. Overall, many customers have used the bars leaks gearbox additive for more than a few months without any complaints, and it shows no sign of giving up.

• This can be added to top-off existing low fluid level, or when changing oil.
• You asked for a heavy-duty professional grade gear repair formula, and you got it.
• Seal conditioner – stops currents and prevents future leaks by protecting and reconditioning seals.

Best With Commercially Available Gear Oils: Liqui Moly Gearbox Additive

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Next on the list, we've got yet another additive that manages to win our hearts. It's the Liqui Moly Gearbox Additive and it's widely considered as one of the most convenient additives you can buy. The liqui moly gearbox additive reduces oil loss via leaky seals, prevents oil spots and pollution of the environment. The Manufacturer says: And we have been raising the bar in terms of quality and service for 60 years. In addition, this is made from raw material deliveries, to production, right through to shipment.

Most importantly, the liqui moly gearboxadditive protects clutches from escaping oil, prevents deficient lubrication and damage to the transmission due to the oil level being too low.

Overall, many have used the liqui moly gearbox additive for more than a few months without any complaints, and it shows no sign of giving up.

• The Manufacturer says: an impressive result that reflects both our exceptional quality and our continuity.
• Prevents transmission oil leaking onto clutches.
• Protects from deficient lubrication and transmission damage.
• Secures optimum lubricating action and increases operational reliability.

Best For Extreme Conditions: Motul Gearbox Additive

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If you often find yourself confused about appropriate and satisfactory additive,s Motul Gearbox Additive should be your first option for buying. In addition, it is good for country of origin and it is for extreme pressure. Make sure this fits by entering your model number. Lastly, the motul gearbox additive is ideal for extreme conditions.

• Extreme pressure, anti-wear, anti-corrosion and anti-foaming additives.
• Package dimensions: 10.4 h x 10.6 l x 12.5 w (inches).
• Good investment for the long term.

Best For Smoother Shifts: Cerma Gearbox Additive

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The Cerma Gearbox Additive is capable of outshining several other additives featured in this list in overall features for the price point. The cerma gearbox additive has seen measurable improvement and it makes it much quieter. Make sure this fits by entering your model number. In addition, it is ideal for all uses, including auto,s diesel truck, motor homes and commercial vehicles. Lastly, the cerma gearbox additive restores performance and fixes many transmission issues.

Almost all buyers found that the additive protects every metal surface being lubricated. In addition, they also found that the additive is used to make a bang. And, a few also found that the additive does not mix with any oil and it in fact causes no seal degradation. Therefore, most customers find the additive is functionally comfortable and no one questions it.

• This is ideal for all uses, including cars, diesel truck, motor homes and commercial vehicles.
• This will not allow the formation of performance degrading sludge and varnish to form.
• Eliminates most seal leaks and lowers operating temperatures in hard-working units.
• This restores performance and fixes many transmission issues.