Picture 1 of 1
Picture 1 of 1
Genuine GM ACDELCO Coolant System Sealing Tabs 12378255
M
magdy-to-trade (41)
97.7% positive feedback
Price:
$9.06
Free shipping
Returns:
30 days returns. Buyer pays for return shipping. If you use an eBay shipping label, it will be deducted from your refund amount.
Condition:
- Buy It NowGenuine GM 12378255 Fluid 3634621 Cooling System Seal Tablet - 4 Grams Pack of 5
Oops! Looks like we're having trouble connecting to our server.
Refresh your browser window to try again.
About this product
Product Identifiers
BrandGeneral Motors
Manufacturer Part Number12378255
eBay Product ID (ePID)3017360824
Dimensions
Weight0.07lbs.
All listings for this product
Ratings and Reviews
Most relevant reviews
- Feb 20, 2019Top favorable review
Really Works!
I had the infamous engine manifold coolant leak that Ford had so generously designed into its cmax model (2013). It had been getting progressively worse over the last 2 years of owning this car. It was getting to the point where I had to add coolant basically every week. When I came to a stop, I had to turn off my environmental controls inside the car or I would be smothered by the smoke rising from the exhaust system where the coolant that was streaming it off the engine would pour onto the hot pipes. Once I received these, and just before heading to the store, I put 2.5 of these tablets into the coolant reservoir, and drove off. The results were nearly instantaneous. The smoke, that I normally would see pouring out from under the hood when I would come to a stop, was completely gone. I could barely smell it anymore when stopped. Awesome product! Even if it stops working at some point, it's much cheaper than buying $13 gallon jugs of antifreeze every couple weeks.Verified purchase: YesCondition: New
- Jan 01, 2018Top critical review
Did not work
I installed these in a 1999 altima that had a externally seeping head gasket. When the engine was cold the coolant would pool up on the top of the transmission. When the engine was warm it would not leak at all. These did not make any difference in the leak at all. They may work for other small coolant leaks but they did not work for my particular use.Verified purchase: YesCondition: New
- Aug 28, 2023
great product probably cost millions to develope
works well on a number of coolant leaks without plugging anything else upVerified purchase: YesCondition: New
- Jun 24, 2019
Great for using with rebuilds.
Hard to find in stores. Use 2-3 of these when rebuilding an engine. they dissolve into very fine particles, great for sealing head gaskets.Verified purchase: YesCondition: New
- Jul 26, 2021
Good for aluminum engines
Recommended by GM for 80´s aluminum engines. I am using them in these engines with no problems so far. This is to prevent cooling problems due to casting porosity and not for repair existing issues.Verified purchase: YesCondition: New
- Jan 21, 2020
Good price and OEM product.
These work great for small leaks. GM recommends You use these when You do a coolant change.Verified purchase: YesCondition: New
- Jul 11, 2025
Great item, a time tested coolant leak f...
Great item, a time tested coolant leak fix good for emergencies.Verified purchase: YesCondition: New
- Jan 30, 2018
Cooling tabs.
My four-cylinder engine was leaking coolant in it into the engine. Someone recommended these coolant tabs. I drink most of the coolant out of the vehicle. I was guessing it was a head gasket issue. And I don’t have this issue anymore if fixedVerified purchase: YesCondition: New
- Nov 16, 2023
Good cooling system maintenance tablets.
Good quality tablets to help with minor coolant leaks.Verified purchase: YesCondition: New
- Dec 05, 2018
Good Value for small cooling system leaks
Developed for GM cars this stop leak will help stop small cooling system leaks. It will not stop big leaks but if you have a small hole in your cooling system or heater core using these may help and avoid a costly repair.Verified purchase: YesCondition: New
