Best Oil Stop Leak Additives: Protect Your Fuel System
Fixing an oil leak can be quick and easy thanks to oil stop leak additives.
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BY Noelle Talmon / LAST UPDATED ON September 21, 2021
Best OverallLucas Oil 10278 Engine Oil Stop LeakCheck Latest Price
Best ValueATP AT-205 Re-Seal Stops LeaksCheck Latest Price
Honorable MentionLiqui Moly Oil Leak StopCheck Latest Price
Honorable MentionBar’s Leaks Engine RepairCheck Latest Price
Honorable MentionBlueDevil Oil Stop LeakCheck Latest Price
Oil stop leaks are designed to stop and seal leaks caused by general wear and tear in your vehicle's engine. Over time, the engine will start to degrade, and you will have to repair it. The good news is that a high-quality oil stop leak is a relatively easy solution for certain issues. It can stop leaks as well as prevent them from occurring. There are many options available in stores and online, so it can be challenging to choose the right one. Check out the list below for some of the top options currently available.
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Benefits of Oil Stop Leak
- Protect the seals. Over time, the seals on the engine can harden and dry, which is the main cause of oil leaks. An oil stop leak can treat the rear main seal as well as the head gaskets so they regain their flexibility. This will prevent the oil from leaking.
- Protect your vehicle and the environment. Oil leaks can be costly, and they're not good for the environment. They can also cause problems with your vehicle. Constantly replacing your oil can add up over time, and your engine won't perform as well.
- Avoid the mechanic. You may choose to visit your local garage if your vehicle is leaking oil. It can be costly to pay for the diagnosis as well as the labor costs. You will save a lot of money if you choose to fix the oil leak on your own.
Types of Oil Stop Leak
Initially, motor oil leak sealers were designed to clog the hole where oil was escaping. Each company had its own way of doing this—some of the earliest formulas used ground peanut shells as a block. The ground particles would flow to the leak and clog the area to save oil. The problem with these particles (as well as formulas that use sawdust, aluminum shavings, and other additives) is the long-term effects on a motor. They increased engine wear and would eventually do more harm than good.
The best engine oil stop leak additives you can buy are made to absolve into all the seals in the engine. Since these formulas do not have engine clogging particles, they don't come with the same harmful effects. The solvents expand and rejuvenate the gaskets and components to their original size and flexibility, so any leaks caused by gaps or deteriorated seals will once again be closed. Older formulas used petroleum distillates to achieve this result. Newer stop leak oil treatments use different chemicals as the distillate can further deterioration in the engine.
One of the most recognizable names in the automotive field is ATP. It first started in a Chicago plant back in 1955. Since then, it has gone from selling replacement transmission parts to producing a large selection of filter kits, repair kits, cables, flywheel and ring gears, cabin air filters and chemicals. The ATP AT-205 is a favorite among consumers.
One company that has been focused on helping customers be their own at-home-mechanic is Bar's Leaks. This U.S.-based company has over 70 years of experience with eliminating engine leaks. The company works with experts in their field to continually deliver high-level results with easy-to-use applications. The Stop Leak Concentrate is a best seller.
Forrest and Charlotte Lucas started their company in 1989 with the goal of producing high-quality lubricants and additives. Lucas Oil got its start in Corona, Calif. The couple quickly grew the company, which has established itself as a prominent fixture in the market. Lucas Oil Stop Leak is available in both gallons and quarts.
Two of the best engine oil stop leak products available are Engine Stop Leak and High-Mileage Stop Leak, produced by STP. This company is headquartered in Connecticut. In the past 60 years, it has become one of the most trusted names in automotive care.
Oil Stop Leak Pricing
- Under $25: To test out whether your issue can be fixed with oil stop leak, you should invest in the smaller options. For under $25, you can get any of the best engine oil stop leak additives in small quantities like 8 ounces and 24 ounces.
- $25 and up: For continued protection, most oil stop leak additives are available in bulk quantities. This can include gallons, packs of 32 ounce containers, or even bundles of gallon containers. Larger quantities are a good option if you know your issue can be fixed with an additive.
Since the most common cause of an oil leak is gaps between the various seals, having a stop leak additive that rejuvenates the seals is essential. This is usually a chemical process that will bring cracked rubber pieces back to their original sizes. Each company will have a different way to achieve this, but chemicals that are most effective are called plasticizers.
A common chemical used to revitalize gaskets is petroleum distillates. The issue with this chemical is that it can have adverse long-term effects on your engine. It can wear out parts of your fuel system while it works to fix others. Over time, this can become more expensive than the original issue. Petroleum distillates are something you want to avoid in a good stop leak additive.
- Compatibility. Possibly the most important factor when considering an oil stop leak is whether or not it’s compatible with your vehicle. Some formulas will not be able to work with diesel engines, and others will not be able to work with synthetic oils. Every product will list the types of engines and fuel system they're compatible with.
- Efficiency. For an engine oil stop leak to be cost efficient will depend on how much additive is required to add and how long it lasts. Additives that require a smaller amount to be mixed with your engine oil will be more efficient long term. An oil stop leak that will keep your seals revitalized for more extended periods will also save you money in the long run.
- Activation. Allowing your engine oil stop leak to activate fully is essential to fixing leaks. The additives will start to activate once added into the engine oil, and usually, they require a few hours. However, even after sitting for the required amount of hours, the solution may need to run through your fuel system for 100 or more miles to reach its full potential.
Best Oil Stop Leaks Reviews & Recommendations 2021
- Consult a mechanic if the problem isn't solved after you use an oil stop leak. If your engine loses a lot of oil, it can sustain a lot of damage. It's vital that you diagnose and fix the problem sooner rather than later.
- Read the product description to make sure you use the proper amount when you mix the oil stop leak with your oil.
- Determine whether your vehicle uses conventional or synthetic oil before making a purchase. While many can be used with different types of oils, it's important that the product is compatible with your particular oil.
- Some oil additives include harmful chemicals. These additives can do long-lasting damage to your vehicle's engine. Avoid any oil stop leaks that use petroleum distillates and look out for products that are certified by the EPA.
Q: How do I use oil leak stop fluid?
Oil stop leaks are easy to use. Simply mix it with the oil you traditionally use in your car or truck. Make sure to properly measure the amount you need. You can find this information on the container of the stop leak fluid.
Q: Is oil stop leak bad for your engine?
Some old-fashioned oil stop leaks were not good for engines. Modern technology has caused the creation of better formulas, so today's products should work just fine. However, if you use the wrong oil stop leak, it can cause engine damage, so make sure to do your research and choose the proper additive.
Q: What if the oil stop leak doesn’t work?
Oil stop leaks are a great solution, however, they aren't designed to fix all issues. Should you use a product and don't notice an improvement, take your vehicle to a mechanic so he can properly diagnose the problem.
Q: Can oil stop leak be used instead of going to a mechanic?
Maybe. That depends on what is causing the oil leak. Oil stop leaks are designed to revitalize gaskets and seals to minimize gaps that cause leaks. However, if you have a large hole or a lot of engine damage, an oil stop leak will not solve the problem.
If you’re looking for universal protection, then Lucas Oil 10278 Engine Oil Stop Leak is the best engine oil stop leak product on the market.
Customers who want to stop leaks and save money should use ATP AT-205 Re-Seal Stops Leaks.