Does coolant have a shelf life ???

[jays58]

Knowing that I'm planning to do a coolant flush on my '02 Tiger, one of my riding buddies gifted me with a couple quarts of Honda brand pre-mixed coolant that is a good 6 - 8 years old.  It is still in the original sealed bottle, but I'm just wondering - is there any reason it would lose any of its' properties over time?  I'm thinking it should be fine - but  I'm just wondering if anyone knows of any reason I shouldn't  use the stuff?  Thanks for any help!  ---Jay

[Goober]

I googled this recently since I too have some old coolant.  Here is quote from Havoline's website:

"The primary limiting factor in the shelf life of a coolant is silicate instability. Since silicate will eventually polymerize to silicate gel, all traditional coolants have a shelf life of about 18 months."

I saw other numbers that varied from 1-5 years from other manufacture's websites.

[jays58]

Goober;  Thanks for sharing your research.  Looks like I'll be buying some fresh stuff!   ---J