Question about shelf life of antifreeze

[tom in boise]

I have a 2006 Chevy Duramax diesel truck. I had the radiator hoses replaced and the coolant flushed and refilled 11 years ago, in April of 2013. At that time the truck had 111k miles on it. Fast forward to now, it has been 11 years and the truck has 165k miles, so 54000 miles on the coolant. When I had it flushed back then, I used this Delo coolant:

I bought a case then and still have an unopened gallon of it. I am going to drain and fill the system using the same coolant. Do you think I can use this leftover gallon as part of the fill, or should I recycle it and just buy all new.

Also, is it worthwhile pulling a sample of the antifreeze and sending it to Blackstone for analysis, as maybe the coolant doesn't need to be replaced?

Your opinions are appreciated.

 

[SHOZ]

As long as it's sealed I would think it's OK. Doesn't really deteriorate on the shelf.

 

[Oillover]

Use with confidence.

 

[BHopkins]

It is my understanding that engine coolant is good for a very long time. And it is easy to determine if it is still good, by testing it.

 

[wpod]

If it is in the container it is not subject to the heat and metals causing a chemical reaction .

 

[JeffKeryk]

Timely post. A friend helped me clean out my shed today; an old friend, who is no longer with us, left a bunch of stuff including 2 unopened jugs of Peak antifreeze.

He can use them as he needs to service his 1955 Ford PU.

 

[JHZR2]

The inhibitors don’t get consumed unless facing the active metals under the right conditions. If there are stabilized components, like silicates, they can destabilize and drop out. Agitation doesn’t repair the surface stabilization that put them into suspension….

But generally I wouldn’t be that concerned.

 

[Snagglefoot]

As an aside, you might check the fine print on the back of the jug. The current Delo ELC suggests 750,000 miles but those are expressed as trucking miles in big rigs. The suggested maximum time is 8 years. This has nothing to do with the stuff in the jug. I would use it.