10 Best Exhaust Sealant

I have been cOkay, I screwed up. When I initially reviewed this, I complained that it dried hard and virtually impossible to remove. I was wrong. After finally being able to pry off the plastic item I glued to plastic in my car, I discovered the glue was, in fact, still flexible. So, if you are looking for a glue that stays flexible yet has incredible grip, this is it. If, however, you chose this with the idea of being able to easily remove it later, forget it.

I bought this for replacing the knock sensors on my 2001 GMC Sierra which had a design flaw and needed this stuff to build a water dam around them after replacing the rusted one.

I first cleaned up the area till it was spotless – preparation is key with any adhesive or paint! It goes on easily and you can use a wet finger to contour it and smooth it out.

It cleans up easily when “wet” using shop towels and isopropyl/rubbing alcohol.

If you replace the cap and pull out the cured silicone plug from the nozzle you can use it repeatedly.

I ended up needing it for another fix one month later and it was still good. In fact, I’m going to order another to keep as a spare for repairing stuff, because it’s extremely handy for any small fixes that could use some water-tight electrically-insulating silicone sealant.

Good bond for medium high-temp applications. I haven’t had the same trouble with cure inside the tube after opening that I’ve had with other brands. I’ll be using this going forward.
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Update – I’ve gone through a couple of more tubes now and this is definitely my favorite product of this type. It has a better bond that other black silicone RTV products I’ve used. Definitely a different odor but maybe that has something to do with its superior performance. I’ve used it for oil-resistant gaskets on my motorcycle, various electrical applications as an insulator with high temperature bond strength, to secure thermocouples that go up to 500F, and other miscellaneous applications where I need an elastomeric bond that will withstand water and high temperature.