REVIEWS

I have a 2012 Toyota Camry Hybrid that started having serious overheating issues around 130k miles. I replaced the water pump, thermostat, and fan, but it would still overheat on the highway anytime I went over 80 mph. At about 148k miles, I tried Blue Devil head gasket sealer, which got me another maybe 1,000 miles before misfires started (especially on cylinder 4). I replaced the coil on that cylinder, then tried K-Seal, but problems kept piling up—hybrid battery failed (replaced that too), then the rest of the coil packs and all four spark plugs. The car would run great for short periods, but misfiring returned badly, especially during transitions from electric to gas engine, and soon I had a ton of check engine lights.

I was ready to give up on the car after sinking so much money into repairs. Then I found Thermalweld online and called them. The technical support guy was incredibly helpful and patient—he walked me through the entire process step by step. First he helped me unclog the heater core caused by the previous products I used. After that, I flushed the the system with water and added the Thermalweld. I drove 50–100 miles as instructed. Finally, I flushed everything out again and refilled with proper coolant.

The results? No more misfires, no overheating, no check engine lights—the car runs like new again! It feels smooth and reliable, just like it did years ago. After all the other products and repairs that only gave temporary fixes (or none at all), Thermalweld actually solved the root issue.

I couldn't be happier—this product literally saved my car and a ton more in mechanic bills. Dave's guidance and superior customer service were top-notch; he was available, knowledgeable, and genuinely cared about getting it right. Highly recommend Thermalweld if you're dealing with a blown head gasket or similar cooling/engine problems—especially on a hybrid like mine. Worth every penny!

Thank you, Dave and Thermalweld team!

Thanks Daniyal for the nice review, so glad everything worked out.

I wanted to take a moment to express our sincere appreciation for your outstanding head gasket solution. We’ve been using your product for over eight years now and have seen countless success stories during that time.

One of the most remarkable examples was a Mercedes-Benz V12 we worked on, where both the owner and our team believed an engine replacement was the only option. However, after applying your solution, that vehicle has been running strong for over three years now — and it’s driven aggressively. The results truly speak for themselves.

Your product has proven to be reliable, effective, and a real game-changer for our operations. Thank you for providing a solution we can trust and stand behind.

Hopefully all is well with you and the team Still interested in a south eastern promotion campaign and would like to experiment with an Audi Q7 project soon

Warm regards,

Glen A

Armour Automotive Group

Thanks Glen, we appreciate your business.

Used on a third gen prius with 200k miles and fixed it right up! Stopped misfiring and shaking immediately and no more white smoke. Also used on a 2018 prius with almost 300k and worked perfectly

Went by the instructions, everything worked. Unfortunately i did not get the bypass hose clamp tightened, hose came off and car overheated before I could get off the highway. After cooling down, put in 2 gallons of coolant and no issue since.
Called Teck support, very helpful. Advised to continue driving for another week checking coolant level which will determine if I need to reapply. Very satisfied with product and support.

I have just installed the product. No more bubbles returning to my resorvior, Initially after the first ten minutes the bubbles continued although reduced. I turned off the engine.Two hours later I ran the vehicle on high rpm for ten more minutes. No more bubbles. Corrected fan blower as this was the intial cause of overheating.

Great stuff! I had some problems little confused. But the Technical Support staff was more than happy to walk me through it. I have had no problems since using it. Highly recommend Thermalweld

Greetings, we are glad everything got resolved.

I tried a different product which did not work. I had great customer service and support. The tech had knowledge about my vehicle, 93 Cadillac Seville, gave me advice on maintaining it beyond the treatment, and understood the intricacies of the NorthStar motor. The instructions were simple to understand and the product worked as promised. Thank you!

Great service and product had a $5500 quote repair bill from Subaru this product fixed the seal.

I’d purchased a 2001 DeVille hearse with the Northstar engine. Bought it knowing it had an overheating issue. I’m no mechanic and didn’t know the Northstar engine history. I was repeatedly told to junk the car as it was not worth fixing. I saw a video of Thermalweld on YouTube. I followed their instructions exactly. I am now a happy customer ! I drive my car daily. Almost 10,000 miles later and NO overheating issues! Thank you , Thermalweld !!

I've used thermalweld on vehicles starting back in 2022 and it is the best head gasket repair sealant on the market as far as I'm concerned. And every one of the cars are still running great today.