Antifreeze/Coolant Change Intervals

[danachevroletfor1967]

I have a question for you guys that I'm sure have more experience than me related to car things. I have a 1978 K5 Blazer that I had the antifreeze/coolant changed in 2022 with Prestone's longer engine life coolant (10 year or 300,000 mile guarantee). Now I know I'm never going to approach 300,000 miles. My question is do you think this antifreeze/coolant would be alright to leave in for say 5 years? I've often heard that the anti freezing and anti boil over properties last for decades. It's what is added that wears out over time or mileage, such as anti-corrosives and lubricants that require the frequent changes. My owner's manual says to change the antifreeze/coolant every 2 years, but I'm sure today's are much improved over 47 years ago. I drive the Blazer no more than 500 miles a year.

What do you guys think? Any advice appreciated.

[Ralph Spears]

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[frankk]

Myself, I would change it out after 5 years. It's not a hard job to do and not expensive

[Burd]

I’d at last drain out the Rad and replace, the coolant, there is water pump lube in the coolant that’s prob wore out. Plus a good time to clean up the overflow bottle too, I cane up,w/ a process to clean the inside nice.

[danachevroletfor1967]

Originally Posted by Ralph Spears

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How old is that can? I don't remember Prestone in anything but their bright yellow containers, metal then plastic.

[Ralph Spears]

.. You must be a young guy if you don't remember the can before they used plastic jugs price is $1.49