ACDelco GM Original Equipment 10-108 (12378255) Cooling System Sealing Tabs - 4 g (Pack of 5)

I have a 2013 Prius, 3rd generation . 210,000 miles. It had been running perfect, when it developed very rough engine noise and severe shaking from time to time when starting. Once underway the car ran normal. A couple of well reviewed mechanics were unable to figure out the cause of the problem. One even said the engine had something lose inside and wasn't worth fixing and should be sold for junk. That made no sense to me. Said he would give me $500 for the car as a trade on one of the used cars he had for sale. The other mechanic said he was certain the head gasket was not leaking (I suspected it was the problem until I got that advice) The check engine light came on and the code said the problem was with the #2 cylinder. I decided to use the internet to find an answer. Turns out this generation of Prius often suffers from the head gasket leaking a bit of water often into the number 2 cylinder. It's a somewhat common problem at around 200,000 miles. Number of options. 1, replace engine with a new or rebuilt or use a low mileage engine from Japan. 2. replace the head gasket. Costly options on an older car with lots of miles. fortunately, I came across a retired mechanic who was aware of the problem and suggested as a first and least costly option, I buy and use this AC Delco product to try and stop the leak. Said he used it on his own car with good luck. Said he was into the second year after using it once and no leaks. I bought it and put into the engine per the instructions. It has now been over 1000 miles since I used the product, only one application, and NO PROBLEMS!!! Talk about a cheap and effective fix. Plus it pin points the cause of the problem. So much for considering top mechanics as the last and best word on my problem. Two lessons learned. 1. This a great product so far. If problem shows up again I will just repeat the fix and take from there. Could not ask for more. 2. The internet is wonderful tool to use to help solve a problem, if only you will take the time and effort to use it fully.

Worked for me within a 20 minute drive, I have a turbo LS truck and put in a new radiator and water pump and hoses and had a small but annoying leak I could not find for anything! these things arent magic in a bottle but its a really cheap way to try the easy way out and if not then oh well you are out a couple minutes and couple dollars and keep going forward….

These work awesome! Do not bother with the other stop leak products!! I used a few of these to stop a leak in a 2005 Honda Element heater core months ago for a broke friend. Saved them a $800+ shop bill. Stopped the overheating issues due to coolant loss. Excellent product!!!

These are Effective at Stopping Minor Leaks in The Cooling Systems Of Vehicles. Follow The Directions!

These things have been around since the dawn of time. GM used to put these in new cars off the line during the LIM-gasket fiasco. They work as intended most of the time and can even be a permanent repair in certain cases. I had a slight external head gasket leak from a crossover coolant port. The leak was tiny, a seep at best and these took a good little while to actually seal up such a tiny leak but they did after a couple hundred miles. The product works most of the time (within reason) and is worth a shot before doing more expensive repairs. My only complaint is the shipping from Amazon, once again they fumbled the packaging and shipping. They sent me an open package with one of the tabs completely missing. The envelope wasn't breached so it had to have been packed that way. Another one of many Amazon shipping gripes.

2014 Sierra - I had a very small radiator leak that I could smell but it did not drip enough to get to the ground. This fixed it, no longer smell it and quit losing antifreeze.

Stop small leak on my 3.5 honda vtech where the seal was leaking on the water tubing from the water pump to the front housing under the intake manifold... on my sandrail...

Product works excellent would purchase again

Best product

J'avais peu d'espoir car j'avais une bonne fuite du radiateur,mais sa fonctionne a merveille

اوقف التسرب من اليوم الأول بعد معاناة لسنوات - شفرولية كروز ( يجب طحن المنتج ووضعة في الراداتير مباشرة أو في الخرطوم العلوي الواصل للرادتير لو دورة التربيد مغقلة ) ممنوع تضعة في قربة المياة

Great

Work great best stop leak I've ever used in 60 years !!