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The 8 Best oil additives to stop leaks of 2025

Are you trying to find oil additives to stop leaks among various brands on the market but aren’t sure where to begin? To assist you in finding the right one, we’ve put together a list of the 7 best to help you pick the perfect one!

We investigated and evaluated a number of the top-selling oil additives to stop leaks on the market in order to create our list of the best. Making a decision among the many options available is never simple. There are an infinite number of models available, each with a distinct price. And as you’ll find out, the best options aren’t usually the ones you imagine! This comparison is rich and relevant because of the numerous factors that were employed. You will find products featured in this ranking not only based on their pricing but also on their features and other customers reviews. To write this review, we completed 10 hours of research and did 41 oil additives to stop leaks tests. You won’t need to pick products at random any more. If you’re unsure of what to look for, browse our list and consult the buying guide!

An overview of our top picks

Table of contents

The best oil additives to stop leaks you can buy today

SaleNo. 1
Lucas Oil 10278 Engine Oil Stop Leak - 1 Quart
  • Product Type: Auto Oil
  • Package Dimensions: 8.89 L X 10.16 W X 30.48 H (Centimeters)
  • Package Weight: 0.953 Kilograms
  • Country Of Origin: United States
SaleNo. 2
Lucas Oil Engine Oil Stop Leak Top Off Additive/12x1/Quart
36 Consomer Reviews
Lucas Oil Engine Oil Stop Leak Top Off Additive/12x1/Quart
  • Long lasting
  • Conditions seals and o-rings to stop oil leaks
  • Contains state-of-the-art components to reduce friction and wear and extend engine life
  • Effective seal swell agents are used to condition hard and shrunken seals and gaskets
  • 1 quart treats up to 6 quart capacity
No. 3
Bar's Leaks 1010 Engine Oil Stop Leak Concentrate, 11 oz, 1 Pack, Grey
  • STOPS AND SEALS MOTOR OIL LEAKS: Bar's Leaks Engine Oil Stop Leak Concentrate is specially designed to stop seal and gasket leaks caused by normal engine wear and age.
  • RESTORES GASKETS AND SEALS: One bottle treats up to 5 quarts of oil. For larger systems use 1 bottle for every 5 quarts of oil capacity. On small 4 cycle engines, use approximately 2 ounces per quart of capacity.
  • PREVENTS ENGINE OIL LEAKS: Add entire bottle of stop leak to engine oil at or between oil changes. Leaks usually stop in 200 miles or 3 days of driving. If leak continues, a second application may be required or mechanical attention is needed.
  • WORKS WITH ALL ENGINE OILS: Works with ALL gasoline and diesel engines using conventional, high mileage and synthetic engine oil.
SaleNo. 4
Bar's Leaks OS-1 Oil Seal Engine Oil Burning and Leak Repair, 16.9 oz.
  • REPAIRS LEAKING MAIN SEALS AND GASKETS: We have designed this product to work in all gasoline and diesel engines including turbocharged, EcoBoost, hybrid and even racing engines.
  • RENEWS WORN VALVE SEALS AND GUIDES: Your vehicle is a good candidate for Bar’s Leaks Oil Seal Engine Oil Burning & Leak Repair if it does not consume more than one quart of oil per day.
  • STOPS OIL BURNING & BLUE EXHAUST SMOKE: This covers 3, 4, 5, 6, 8 and 10 cylinder engines in all cars, trucks, vans and SUV’s. Our product can also be used in heavy-duty applications referencing the appropriate dosage level.
  • SEAL ALL OTHER OIL LEAKS, DRIPS AND CONSUMPTION: This applies to a wide range of other motor applications too - tractors, boats, RV’s, motorcycles (including wet clutch), ATV’s, lawn equipment.
  • MADE IN THE USA
No. 5
Bar's Leaks 1334 One Seal Stop Leak - 11 oz
  • WORKS WITH ALL ENGINE OIL, TRANSMISSION FLUID AND POWER STEERING FLUIDS: Bar's Leaks One Seal multipurpose stop leak effectively seals all minor engine oil, transmission and power steering system leaks.
  • SAFE AND EASY TO USE, GUARANTEED: One bottle will treat one engine oil, transmission fluid or power steering fluid system leak.
  • 3X SEALER: It’s specifically designed to stop seal and gasket leaks caused by normal wear and age.
No. 6
Engine Wizard - Engine Oil Stop Leak (1oz) Engine Treatment, Stop Leaks and Stop Smoke without Needing to Dismantle
  • Quickly Fixes Oil Leaks: Often resolving the issue within just 30 miles of driving. Includes online customer support to help diagnose your leak problem through photos.
  • Eliminate Blue Smoke: Resolves blue smoke issues within seconds, delivering noticeable improvement for oil loss problems. If the issue persists, we offer a 100% refund—guaranteed.
  • No More Chaos: Say goodbye to constantly topping off oil! Effectively reduces oil leaks and burning oil issues, significantly minimizing oil loss and keeping your engine running smoothly.
  • Highly Flexible: Compatible with 3, 4, 5, 6, 8, and 10-cylinder engines across all cars, trucks, vans, and SUVs. Whether it's black smoke issues or excessive oil consumption, this product delivers remarkable improvements.
  • Easy Application: Simply add Engine Wizard to your engine oil for a hassle-free way to maintain and extend the life of your vehicle's engine.
SaleNo. 7
Bar's Leaks 1000 High Mileage Engine Repair, 16.9 oz | Restores Performance, Increases Compression & Horsepower, Stops Leaks, Noise & Smoking
  • RESTORES PERFORMANCE: Contains a combination of the best performance additives to repair the most common oil-related problems
  • INCREASES COMPRESSION AND HORSEPOWER: Restores lost compression and power, reduces noise and oil consumption, while improving the performance of worn cylinders, rings, bearings, and seals
  • STOPS LEAKS, NOISE, AND SMOKING: For most vehicles, this is your last chance before paying an expensive repair bill or replacing the vehicle
  • FRICTION MODIFIERS: Engine Repair can be used to top off the existing oil when low, or add a bottle when changing the oil and filter
  • REPAIR-IT: Engine Repair-It can be used to top off existing oil when low or add a bottle when changing oil.
No. 8
Permatex 30302 Engine Oil - Stop Leak, 12 fl oz, Effectively Stops and Prevents Oil Leaks and Burning Without Needing to Dismantle
  • Reliable and Cost Effective: Cost Effective Alternative For Fixing Leaks In Your Vehicles Engine System, Suitable for All Gasoline and Diesel Four-Stroke Engines.
  • Stops and Prevents Future Leaks: Perfect Solution for all small to moderate Engine Oil Leaks, Effectively Stopping and Preventing Engine Oil Leaks and Oil Burning Without Dismantling The Engine.
  • Long Lasting Seal: Provides a Long-Lasting Seal for Engine Oil Leaks, Reduces Blow-By, and Revitalizes Rubber and Neoprene Seals and O-Rings, for a Smooth and Uninterrupted Ride.
  • Stop The Mess: If You Are Tired of Constantly Adding Oil To Your Engine or Dealing With Messy Oil Leaks, the Permatex Engine Oil - Stop Leak is the Perfect Product For Your Garage.
No. 9
LIQUI MOLY Motor Oil Saver | 300 ml | Oil additive | SKU: 2020
  • Reduces oil consumption via the piston rings and valve guides
  • Prevents blue, smoky exhaust fumes
  • Prevents leaks due to leaks at elastomeric seals
  • Regenerates engine seals made of plastic and rubber
  • Prevents pollution of the environment due to oil dripping from the engine
No. 10
XADO ATOMEX Oil Additive Stop Leak Engine - Restore Seal and Gaskets, Treatment for Car Engine High Mileage or Rear Main Seal, Best Stopper Leaks Reseal (Bottle, 250 ml)
  • Elasticity Restorer: Look no further for a solution to restore elasticity ability of rubber gaskets and seals. Say goodbye to leaks and fugas with our formula for complete rejuvenation and protection.
  • Leak Prevention: Ideal for stopping engine oil leakages. Engineered for all engines, including auto and motorcycle, our slick liquid formula fixes leaks and rejuvenates seals.
  • Cost Saver: It offers complete protection for older and new engines. This multi-purpose aditivo is perfect for stopping leaks, enhancing engine performance, and extending the life of your vehicle.
  • Efficiency Enhancer: Reduces engine noise and oil consumption with our advanced formula.The slick liquid fix rejuvenates seals, valves, and cylinders, ensuring smoother operation and reducing wear.
  • Universal Compatibility: This multi-purpose sealant works with auto, motorcycle, and marine engines, preventing fugas and leaks while rejuvenating seals, valves, and cylinders.
No. 11
LIQUI MOLY Gear-Oil Leak Stop | 50 ml | Oil additive | SKU: 1042
  • Reduces oil loss via leaky seals, prevents oil spots and pollution of the environment
  • Protects from deficient lubrication and transmission damage
  • Secures optimum lubricating action and increases operational reliability
  • Prevents transmission oil leaking onto clutches
  • Compatible with commercially available gear oils, simple and safe to use
No. 13
Lucas Oil 10279 Engine Oil Stop Leak - 1 Gallon
  • Compatible with petroleum, semi-synthetic and full synthetic motor oils
  • Contains no harmful solvents
  • Reduces engine noise and oil consumption, while raising oil pressure
  • Renews worn seals with no risk of damage or eventual corrosion
SaleNo. 14
Prestone Stop Leak Additive Engine Oil 12 oz bottle
  • Rapidly halts leaks by rejuvenating seals that have become hardened or shrunken. Provides extended engine protection, lasting twice as long as traditional oil-based stop leak solutions. Compatible with all types of motor oils, including synthetic, conventional, and high mileage variants.
  • Container type: Bottle
  • Liquid volume: 12.0 fluid_ounces
SaleNo. 15
ATP Automotive AT-205 Re-Seal Stops Leaks, 8 Ounce Bottle
  • Professional strength fast acting resealer, stops leaks fast
  • Rejuivinates all rubber seals & gaskets in engines, transmissions, power steering, differentials and hydraulic systems
  • Compatible with conventional and synthetic oils, ATF, gear oil, power steering fluids and hydraulic oil
  • Does not contain petroleum distillates, will not over-swell or breakdown seals
  • 8oz bottle will treat a 6 quart capacity, adjust accordingly
No. 16
Bar's Leaks Axle and Differential Gear Repair, 16.9 Oz
  • STOPS PINION, AXLE, OUTPUT SHAFT AND OTHER SEAL LEAKS: This is a treatment additive for use with automotive, heavy duty, agricultural, marine and industrial gear oils.
  • ANTI-WEAR AW AGENTS: Superior anti-wear, anti-foam and anti-corrosion protection.
  • SEAL CONDITIONER: Extends system life by stopping leaks, reducing noise and improving gear performance.
  • PERFORMANCE ADDITIVE BOOSTER: Designed to mix with all synthetic and conventional petroleum GL-4, GL-5, MT-1 gear oil / lube grades including 75W-90, 80W-90, 75W-140, 85W-140 and all others.
  • Manufactured in the USA, this product works in all manual gearboxes, differentials, open & posi axles and more. Stops pinion, axle, output shaft and other seal leaks. Reduces grinding, whining, clunking and protects gears.
No. 17
Bar's Leaks Rear Main Seal Repair, 16.9 oz
  • Seals timing cover, cam seal, rear main and other hard to stop oil leaks
  • Add to engine oil
  • Specifically designed to seal rear main leaks, but also works better than a conventional stop leak on all other leaks
  • Add entire bottle of Rear Main Seal Repair to engine crankcase (where you add oil) at or between oil changes. Do not overfill. Most leaks will stop within 100 miles or 2 days of driving
No. 18
Bar's Leaks Jack Oil with Stop Leak - 12.5 oz
  • Stops Current Leaks And Prevents Future Leaks
  • Works In All Floor And Bottle Jacks And With All Snow Plow Fluids
  • Non-Corrosive, Non-Clogging & Non-Foaming
  • Compatible With All Petroleum Based, Mineral Oil, And Synthetic Fluids
No. 19
Bardahl 3119 Gear Oil Additive + StopLeak - Extreme Pressure Lubricant Extends Gear Life and Stops Leaks by Conditioning Seals - 8 oz. (Pack of 1)
  • Extends gear oil life
  • Conditions seals and eliminates leaks
  • Protects against gear wear and reduces gear noise
  • Improves synchronizer performance to decrease shift effort in manual transmissions
  • Suitable for use in use in all types of manual transmission and differentials that specify standard automotive gear oils or motor oil as the lubricant
No. 20
Lucas Oil 10009 Transmission Fix - 24 Ounce, White
6,067 Consomer Reviews
Lucas Oil 10009 Transmission Fix - 24 Ounce, White
  • The #1 transmission problem solving additive
  • Contains no solvents
  • Can be added to existing fluid without draining any out
  • Effective in an extremely high percentage of cases
  • Extends needed protection to planetary gears
  • Reduces the need for frequent fluid changes, extends fluid life up to 4 times longer
  • A must for motor homes and commercial vehicles
  • Pour one 24 oz. bottle into your existing fluid without the need for draining
  • For larger or heavily worn transmissions, a second bottle may be required
  • In compact or sub-compact vehicles, a 12 oz. bottle is recommended

How to choose a good oil additives to stop leaks

Does the idea of finding a fantastic oil additives to stop leaks make you anxious? When it comes to purchasing this product, specifically when deciding which model to select, has your head been spinning between options? You are not alone if that is the case. We are aware of the pressure involved in the purchasing process!

Your presence here indicates that you are interested in oil additives to stop leaks. Before choosing which product would be the best for your needs after being inundated with information, locate a reliable source with genuine selections. You can get that information from a variety of sources, including buying guides and rating websites, word-of-mouth recommendations from friends and family, online discussion forums where users can share their own experiences, product reviews that can be found all over the internet, and YouTube channels. You can only get the right product through exhaustive analysis. But you realize that’s not always simple. In order to ease your concerns, we have taken the time to develop a list of the top oil additives to stop leaks products available right now. You might be wondering how we came up with the list. How was this buying guide developed?

First, we used our algorithms to gather as much reliable data as we could about these products. To verify all the data gathered, we used both artificial intelligence and a lot of algorithms.
Then, our experts used criteria that are recognized in the business to evaluate them according to their quality to price ratio, allowing us to choose the top oil additives to stop leaks on the market right now!

The selection of the goods is not arbitrary. Before creating a list, we take into account a number of factors. Below are some of the criteria discussed:

Brand Value: What happens if you choose a dubious brand just because it appears to be a good deal? So the likelihood of receiving a product with a short shelf life increases. That is due to the fact that well-known brands have a reputation to uphold, while others do not. Top oil additives to stop leaks brands strive to provide some distinctive traits that set them apart from the competition. So, hopefully one or more of the items on our list will be perfect for you.

Features: Useful features are all you need, not tons of them. We consider the important aspects and select the top oil additives to stop leaks based on those.

Specifications: Numbers always help you measure the quality of a product in a quantitative way. We try to find products with higher specifications, but with the right balance.

Quality: A product’s quality may always be quantified with the aid of numbers. We look for goods with better standards that strike the proper balance. The best quality product that gets highly appreciated and recommended by experienced users.

Customer ratings:  Would it be accurate to suggest that the oil additives to stop leaks were used by hundreds of customers before you? Superior ratings indicate that many customers had better service.

Customer Reviews: Like ratings,  provide you with accurate and reliable information about the product from genuine customers. Customer ratings are very important to all of us because they contain accurate and reliable information about the customer service we received from several hundred customers.

Seller Rank: This is very intriguing! Not only do you need a good oil additives to stop leaks, you also need a product with rising sales that is trendy. It accomplishes two goals. First, the expanding user base proves the quality of the product. Second, given that number, producers must be able to offer greater quality and after-sales support.

Value: You get what you pay for, they say, so consider the value. Cheap isn’t always good and expensive isn’t always bad. However, that does not imply that spending a lot of money on a product that is flashy but underwhelming is a good idea. Before adding them to the list, we make an effort to evaluate how much value you can get for your money from your oil additives to stop leaks.

Durability: Durability and reliability are closely related concepts. You will benefit from a strong and long-lasting oil additives to stop leaks for months and years to come.

Product availability: Products come and go, and new ones replace the old ones. Most likely, a few new features and required changes were made. What use is it to use a supposedly good product if the maker no longer supports it? We make an effort to highlight products that are current and offered by one or more trustworthy sellers, if not more.

Negative Reviews: Yes, we do take that into account as well! The goods with the majority of bad reviews are filtered out and disregarded when we choose the best-rated one on the market.

These are the standards by which we selected our oil additives to stop leaks. Do we end our process there? Hell no. The most crucial fact about us that you should be aware of is that we regularly update our website with current and pertinent information. We have one more layer of filtration since we place the greatest importance on reader satisfaction. Please let us know if any product included here is incorrect, irrelevant, subpar, or simply out of date. We always value your opinions, and we’ll work hard to make any necessary corrections to our list in response to them.

Why should you believe us?

There are now thousands of possibilities for these products on Amazon, but choosing the best one can be difficult and time-consuming. And what oil additives to stop leaks should you purchase in 2022?

This guide is the result of more than 10 years of experience in researching, testing and writing about many topics. Each member of our team is an authority in their area. We read every article we could find online and every consumer review on every retail website for seven hours. Additionally, we discovered a ton of websites that offered helpful resources, including buying tips and thorough information on oil additives to stop leaks.