---
product_id: 23225656
title: "ACDelco GM Original Equipment 10-108 (12378255) Cooling System Sealing Tabs - 4 g (Pack of 5)"
brand: "acdelco"
price: "€ 8.85"
currency: EUR
in_stock: true
reviews_count: 13
category: "Ac Delco"
url: https://www.desertcart.fi/products/23225656-acdelco-gm-original-equipment-10-108-12378255-cooling-system-sealing
store_origin: FI
region: Finland
---

# Multi-surface engine compatibility Instant oil/coolant fill after application High viscosity, air-cure sealant ACDelco GM Original Equipment 10-108 (12378255) Cooling System Sealing Tabs - 4 g (Pack of 5)

**Brand:** acdelco
**Price:** € 8.85
**Availability:** ✅ In Stock

## Summary

> 🛡️ Seal it once, drive worry-free forever!

## Quick Answers

- **What is this?** ACDelco GM Original Equipment 10-108 (12378255) Cooling System Sealing Tabs - 4 g (Pack of 5) by acdelco
- **How much does it cost?** € 8.85 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.fi](https://www.desertcart.fi/products/23225656-acdelco-gm-original-equipment-10-108-12378255-cooling-system-sealing)

## Best For

- acdelco enthusiasts

## Why This Product

- Trusted acdelco brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Trusted Longevity:** Proven fix for high-mileage engines—keeps your ride running smooth and leak-free
- • **Durable & Resistant:** Blow-out resistant and safe against engine oils, coolants, and oxygen sensors
- • **Rapid Assembly Ready:** Fill oil or coolant immediately after torqueing bolts—no wait, no downtime
- • **Universal Engine Fit:** Seals oil pans, manifolds, cam covers & more with professional-grade reliability
- • **Precision Engine Seal:** Pinpoint application for flawless sealing every time

## Overview

ACDelco GM Original Equipment 10-108 Cooling System Sealing Tabs deliver a high-viscosity, one-component RTV sealant engineered for versatile engine component use. This air-cure formula bonds instantly, allowing immediate oil or coolant fill post-application. Resistant to engine oils, coolants, and corrosion, it ensures durable, blow-out resistant seals compatible with oxygen sensors. Ideal for professional-grade repairs and trusted by mechanics to extend engine life and prevent leaks in high-mileage vehicles.

## Description

RTV Engine Sealant is a one-component, room-temperature vulcanizing (RTV) sealant. It is a high viscosity engine sealant that cures when exposed to air. The cured material has adhesion and elongation properties and is effective even on large gaps. It is very resistant to engine oils and coolants, will not corrode metals, and is blow-out resistant. This engine sealant is also oxygen sensor safe. This product comes in a tube for easy, pinpoint application.

Review: Excellent stop leak - Works great without harming system!
Review: Great product. Highly recommend - 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.

## Features

- Engineered for use on a variety of engine components - effective on: oil pan, ladder frame, front and rear covers, t-joints, manifold corners, intake, manifold end seals, and cam covers
- Designed for quick and easy application, assembly may be filled with oil or coolant immediately after applying sealant and torqueing the bolts
- High viscosity product that cures when exposed to air

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0026JK8C8 |
| Best Sellers Rank | #6,336 in Automotive ( See Top 100 in Automotive ) #2 in Automotive Replacement Engine Cooler Accessories |
| Customer Reviews | 4.6 4.6 out of 5 stars (1,223) |
| Date First Available | April 14, 2009 |
| Exterior | Machined |
| Is Discontinued By Manufacturer | Yes |
| Item Weight | 1.12 ounces |
| Item model number | 10-108 |
| Manufacturer | ACDelco |
| Manufacturer Part Number | 10-108 |
| Model | AC Delco |
| OEM Part Number | 12378255 |

## Product Details

- **Auto Part Position:** Front
- **Brand:** ACDelco
- **Color:** Beige
- **Material:** Aluminum
- **UPC:** 036666919363

## Images

![ACDelco GM Original Equipment 10-108 (12378255) Cooling System Sealing Tabs - 4 g (Pack of 5) - Image 1](https://m.media-amazon.com/images/I/71raVEVK6dL.jpg)

## Questions & Answers

**Q: The description states "ACDelco 10-108 COOL SEAL5TABS 24CTN"  Please clarify if this is a CARTON of 24 blister packs or only 1 blister pack w/ 5 tabs**
A: 1 blister pack with 5 tabs

**Q: Will these work with the orange Dexcool antifreeze?**
A: My mechanic said not to put anything into the anti-freeze. I will never use that orange stuff in my 1994 Cadillac 4.9 Deville. If you have the 4.6 North Star, that may be different story. GM tried to promote these tablets to cure a bad leaky North-Star motor. Jeff.

**Q: Is this product preventative ?**
A: Yes, this was actually put into aluminum block engines from the factory because of the  porosity. It does an incredible job stopping leaks and preventing leaks.

**Q: what is a ladder frame?**
A: A ladder frame uses an additional block structure located between the cylinder block and oil pan, which incorporates the main bearing caps into a one piece component resembling a ladder, sometimes called a girdle.Feb 6, 2018

## Customer Reviews

### ⭐⭐⭐⭐⭐ Excellent stop leak
*by J***T on February 25, 2026*

Works great without harming system!

### ⭐⭐⭐⭐⭐ Great product. Highly recommend
*by R***R on August 3, 2025*

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 on 2010 Prius Headgasket!
*by S***H on September 16, 2024*

These tabs worked perfect on my Gen3 2010 Prius with a number 2 cylinder headgasket leak. This is a common issue for Prius between 2010 and 2014 and will show a misfire code in number 2 cylinder, loss of coolant and a rough cold start. Each tablet is equivalent to 4oz and you need 1 to 1.5 oz per quart of coolant in your cooling system. My Prius takes 7.7 quarts. So I crushed two tablets inside a zip lock bag, cut a corner and poured it into the expansion tank/coolant reservoir (since there isn't a radiator cap for the prius) and topped it off with original Toyota long life red coolant. I then drove it around foe about 3O mins cleared the check engine light with my scan tool and and drove it foe about 40mins until it went through and cleared all the monitors. No check engine light!!! Also, the next morning on cold start, no rough idle and car ran smoothly. Saved me a lot of money. Not sure how long it will hold up. Car currently has 250,000 miles. I will report at 260,000 miles to see how it holds up. I wouldn't recommend using more than necessary as it can clog the heater core and you will lose heat and have inefficient cooling when needed. Definitely saved me a few grand of replacing the headgasket. I will replace it eventually. Since it was leaking into the spark plug cylinder, I would replace the plugs as well with original ones from thr dealer and an oil change.

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*Product available on Desertcart Finland*
*Store origin: FI*
*Last updated: 2026-03-16*