I just wanted to see if you guys and gals have used the Coolant Tabs that are put out by GM. I know that GM has used these for the last 20 years because of coolant loss on the Aluminm block and heads, and because of that sorry Dexcool used. I know for a fact that these tabs work. I crushed the package and added them to the upper hose and after about 10 miles there was NO coolant loss and no coolant smell. Now I know this is not a mechanic in a box but it is a great way to stop or slow down a coolant leak. These pellets run about $5 a card and they are made up of vegetable extract so there is no acid to eat away the gaskets

 

GM has had those for more than 20 years, and before dexcool. Perhaps made from ground walnut shells. Expands to fill a small hole. May work for leaks around hoses, etc., in hard to get at spots. If you have a good bit of expansion and contraction can dislodge and start leaking again. Like all bandaids, it is what it is. Won't fix a major HG leak. Can plug the minor leak, then go on to plug the lower tubes of radiator if they were already heavy with calcium (not using distilled water) or Dexcool (makes sludge as breaks down over time and if combined with other coolants). When you have a water soaked sponge just barely oozing liquid, adding a a sealant material converts that to "concrete". A radiator with 1/3 of the tubes plugged is not going to perform when needed in the summer.

You'll notice a lot of the HG stopz leakz products hype that they are just the thing for Caddy Northstar engines... aluminum blocks and heads, cylinder sleeves, and more. We are not alone.

So what problem were you having that prompted you to this solution? And I'm not saying you have not improved things, but you should be aware that effects can last a short time, and other things that you can't see might be effected as well.

 

Well like most Disco's, I also had a headgasket seeping ( right side rear). So being a retired service manager from GM I went and bought a package of the tabs,crushed them up and poured into a radiator hose. In a couple of miles leak stopped and smell of sweet coolant was gone.
Now I know this was a quick fix,but I still went on and had the headgaskets replaced last week. But I would think if it was a emergency and you did have a small leak this would work in a jam. I really do not like all of the stuff that is sold as (Mechanic in a Can) most of it is crap and never works. I am the type of person that if you do the regular services on your auto that it will last forever. I was able to get my 2000 Disco II with only 113000 miles (traded my 2004 Taurus with 214000 miles even trade for the Disco). I was told that everything had been done service wise to it. Even though I was told this I still did them over again to my satisfaction.
Now when we pulled the heads off of mine the valley and the heads were spotless. There was no sign of sludge and we were able to see that it had been serviced on a normal time

 

I agree that it (and some other products) are a good work around. And if the rest of your cooling system is clear, results will be as expected. At the other end of the spectrum we have the previous owner who poured in two bottles of stopz leakz to get to the auto auction, and also had a sludged radiator. We have newbies that post on here about HGs blowing on the way home from the purchase.

 

In my opinion,I really do blame Dexcool. I have seen alot of GM vehicles come into the shop with coolant jugs that were just about stopped up.I know that it states to drain and refill Dexcool every 5 years or 150000 miles but no type of coolant should eat away gaskets and turn into a bowl of oatmeal. I remember back in the early ninety's with Ford and the antifreeze that was used in most of there vehicles was turning into a acid and we were having to do a complete flush and install some type of ground wire to the heater cores so the collant would not eat them up from the inside out. SO it is either the companies are using substandard gaskets,or the coolants being used are using some type of acidic additive. There has been quite a few law suites against GM and the Dexcool brand because of the coolant eating away the silicone gaskets,and just plain stopping up the cooling systems.
The best advice that can be used is JUST DO THE SERVICES BEFORE THEY CAUSE ANY PROBLEMS.