Concentrated Rear Main Seal Repair


  14 Reviews

The engine oil repair formula that made us the #1 brand for all oil leaks stemming from the rear main seal, timing cover, cam seal and anywhere else you’ll find troublesome oil leaks! Millions of bottles sold, and so easy anyone can do it – no technical expertise required. Safe, effective and affordable, and backed by Bar’s Leaks’ reputation as a premium chemical repair company since 1947. We specialize in keeping your car on the road and away from unnecessary expensive repair bills. If you are dealing with an engine oil leak, you’re in the right place.

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Bar’s Leaks is the leader that specializes in chemical solutions for rear main seal leaks and other automotive issues. Our products are effective and affordable. And they’re easy to use, too. If you know how to pop the hood on your car, you can install our rear oil seal solution. We design our products for ease of use, because a good solution isn’t very helpful to everyday drivers if they can’t use it. At Bar’s Leaks, we do everything we can to get you back on the road in good condition just as quickly as possible, by offering rear main seal leak products and much more.

Most rear main seal leaks are caused by a combination of normal wear in the crankshaft and seal combined with the drying, hardening and shrinking of the main seal. Bar’s Leaks Concentrated Rear Main Seal Repair restores the seal to like-new condition, and also contains additives to stop leaks in severely worn seals and crankshafts. Not to mention, it works with ALL gasoline and diesel engines using conventional, high mileage and synthetic oil. We’ve gone to great lengths to ensure that our rear oil seal solution is working for you in all possible ways. You can count on us for a rear main seal leak that takes care of your problems and helps prevent future leaking.

You can trust that our products are the fastest, safest way to get your show back on the road — we’ve been proving that since 1947.


For nearly 70 years, the team at Bar’s Leaks has been working to serve everyday drivers just like you with affordable, easy-to-use, effective chemical repair solutions for a range of automotive problems. These solutions include our oil stop leak products, as well as solutions for cooling systems, head gaskets, power steering, transmissions and much more. While you’ll find plenty of options when searching for a rear oil seal product, you won’t find the same level of effectiveness you’ll get with Bar’s Leaks.

Our products are developed and manufactured in the United States, just an hour outside of Detroit. Our top-flight chemical engineers are always searching for ways to enchance our existing products and to develop new products in response to new automotive innovations and technologies. When you want the best rear main seal leak solution available, look no further than the track record of success at Bar’s Leaks.

Grab your rear oil seal solution today.

Customer Reviews

  14 Reviews
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 14 reviews
by J. Elder - Altanta, GA on Bar's Leaks

This product saved me a lot of money. It made a good car into a really nice car. I'm really sold on the Bar's Leaks Rear Main Seal repair, and I'll sure buy it again.

by Timothy W. - Traverse City, MI on Bar's Leaks

I don't normally do this, but I've found an AMERICAN company whose products actually work, and work WELL!!! So I had to write to thank you for your hard work and integrity in a world filled with automotive charlatans and snake-oil marketing.

Main seal leak stop saved my tractor. Oil leak stop saved my aging Subaru. Rislone keeps all my engines running clean and quiet, even with several hundred thousand miles! And Bar's Leaks has saved several radiators and heat exchangers. In a day and age where money does not go very far, your products help the average joe to keep a leg up, and repairs down, on a consistent basis!! I couldn't have kept three cars going through Northern Michigan's brutal seasons, while putting a kid through college without some help, and that came through in the form of several Bar's Products. Thank you folks, for your excellent products, and for keeping it simple, non-corporate, and integrity-based. Proud to be a fellow Michigander (Traverse City). Keep up the good work. You've got a devoted customer and free word-of-mouth advertising for life. -- Sincerely, Tim W.

by F. H. - Orland Park on Bar's Leaks

I just rebuilt my 1966 442 400 engine. I was apparently rusty on how to properly install the rear main seal (rope style) and it leaked almost from the get-go. I reluctantly put a quart of your product in my engine. I put over 100 miles on it and it still leaked. I was going to pull the engine and do it right at the end of the summer. Two days later I noticed there was no oil under the car when I pulled out of the garage. I couldn't believe it, the leak stopped. No oil anywhere under the car. Un-believeable.

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