Hi
I posted this in the NX forum but I think it is more suitable here in the maintenance forum.
I was thinking to change the coolant on my NX200t-2017 as advised to prevent the coolant from turning acidic by time (Change every 5 years).
My question is if the coolant starts to turn acidic after few years, how to know the coolant I am buying from the dealer is not sitting on his shelf for the last 5 years? Is there a manufacturing date on it (like we see on tires)?
Toyota/Lexus selling a pre-mixed coolant not a concentrated (the concentrated as I read have a 10 years shelf life)
I could be changing the car coolant with an even older coolant.
Any thoughts on this, thank you.

 

I would not worry about it. The maintenance schedule for my Kia says to replace the coolant at 120,000miles or 10 years, and that is coolant in use in the engine. I would think coolant on the shelf in the bottle would have a longer life.

 

New coolant does not become "acidic" sitting on the shelf in a jug. It becomes acidic from absorbing all of the contaminants in your cooling system and hot/cold cycles over time. Unless it's 30 yrs. old, I would not hesitate to use new coolant that is 2-5 years old. In fact, I buy engine fluids when they are on sale, not necessarily when I need them, so I always have coolant/oil/trans fluid, etc. sitting in my garage for extended periods of time until I need them.