Pelletized Heavy Duty Stop Leak


  19 Reviews

Original Pelletized Formula

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Our Bar’s Leaks Pelletized Radiator Heavy Duty Stop Leak is specially formulated to seal larger leaks better than other stop leak products. You’ll find plenty of powder formula radiator stop leak products on the market, but you won’t find a seal coolant leak solution that beats ours in effectiveness. Our Pelletized Radiator Heavy Duty Stop Leak is versatile, too, working safely and effectively on plastic, aluminum and metal radiators, heater cores, gaskets and freeze plugs. It also has a water pump lube that lubricates water pump seals and inhibits the formation of rust and scale.

Simply put, it’s the fast, effective, easy-to-use powder formula radiator stop leak that’s just as simple and straightforward for a regular driver as for an experienced mechanic. Convenient solutions to seal coolant leaks shouldn’t be limited to just those with advanced automotive knowledge, which is why each product in our catalog is designed to meet the needs of anyone who gets behind the wheel of a vehicle.

In under an hour, you can quickly and easily solve that once-dreaded leaky radiator. Give it a try and get your car back on the road in no time.


Not every product that claims to stop seal coolant leaks actually works as advertised. In fact, many of the products actually can make the situation worse. But, at Bar’s Leaks, our powder formula radiator stop leak and other products are developed by the best chemical engineers in the industry. These products are proven to alleviate leaks related to cooling systems, head gaskets, engine oil, power steering, transmission and other vital components. The goal with each product is to get you back on the road as quickly and affordably as possible.

Our history of serving vehicle owners stretches back nearly 70 years. Our status as the industry’s best-known brand has emerged from our long track record of successfully developing products that are easy for everyday drivers to use. Bar’s Leaks manufacturers its products right here in the United States, just an hour outside of Detroit. When you want to mild and moderate stop seal coolant leaks at the fraction of the cost of taking your car to a professional, choose powder formula radiator stop leak from Bar’s Leaks.

Learn where you can find Bar’s Leaks Pelletized Heavy Duty Stop Leak near you

Customer Reviews

  19 Reviews
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 19 reviews
by D. C. Sr. - Hayward on Bar's Leaks

I wanted to write and let you all know that I am so very happy that your product is one that works… I only wish that I would have trusted in this process a little while sooner. My wife’'s van developed a leak that came from the underside of the rear of her engine. After careful inspection by both me and a local repair shop, it was thought that either the intake gasket had failed or the head gasket. I spent two and a half days breaking the entire engine apart and replacing the intake gaskets and putting it all together just to once again see the leak when I was all complete. As frustrated as I was, I went to the local parts store and shared my frustration. They recommended Bar’s Leaks Radiator Heavy Duty Stop Leak. To be honest, I wasn'’t much of a fan of those stop leak products but I sure didn'’t want to spend another $300-$400 on replacing the head gaskets and the intake gaskets (of which I just replaced hoping it was the least of the two projects). I bought a jug of your product serial number 046087000472 and within 20 minutes of running the car, THE LEAK WAS GONE!!! I can’'t believe it!

It has been almost 4 months since I did this weekend project and still no leak! I just wanted to let you all know that you have changed my thinking about Bar's Pelletized Stop Leak. I will recommend your product to anyone who has a leak, before they repeat what I did and spend all that money on a wasted weekend of frustration. Thank you!

by Steve H. - Des Moines, IA on Bar's Leaks

I am an ASE Master Technician and have 25 years of experience. Recently my work truck ('99 Ford Ranger 4x4 3.0) developed a severe coolant leak from a failed timing cover gasket (quite common on the 3.0 "Vulcan" OHV engines). I was a long ways from the shop and it was around 15 degrees out (not warm enough to work outside in my book). Filling the cooling system with coolant took about 5 minutes before the coolant was too low to circulate. I have never been one to use a stop leak product before, but I decided to give it a try. Im glad I did. Stopped up the leak like magic. Worked so well that i haven't had to repair it yet (a month so far). Heat and cooling system still working just fine. Thanks for a great product that delivers!

by M. L. - Pleasanton, CA on Bar's Leaks

I guess this is not a question really, but a testimonial. I work in the fast lube industry, and deal with additives every day. When I had vapor and fog coming out of my vents in my '96 F350 with a Powerstroke Diesel, my heart sank, having replaced it less than 6 months ago with a new core.

I will admit, when the idea of radiator stop leak products came to mind, I doubted it would work. I don't really believe in pour in fix-alls just because of the additives I sell, I don't really believe in. I went out on a limb and got a bottle of Pelletized Stop Leak and poured it in the top hose, after dissolving the pellets in hot water. I poured it in and didn't expect anything to happen. Drove it for 5 minutes, and my windows were fogged up. I cleaned the windows and kept driving. Only a little fogging, and after 20 minutes it was done. Fixed! I couldn't believe it.

I would definitely recommend this to anyone I know. I remain skeptical of other "rebuilds in a bottle" but I would sure buy Bar's Leaks again. Bar's, thank you for making a great product that actually works. Feel free to post this as a testimonial. Love the product!

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