Take the 2-minute tour ×
Motor Vehicle Maintenance & Repair Stack Exchange is a question and answer site for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles. It's 100% free, no registration required.

I recently needed to top-off the coolant on my car, but only used a part of the gallon-sized 100% antifreeze container that it came in - how long is it worth keeping the rest in my garage for future use? does it spoil/turn acidic? it's in a plastic bottle with an air-tight cap.

note: it is currently un-mixed, would it be better to mix it with water now?

share|improve this question

2 Answers 2

up vote 4 down vote accepted

The coolant should not expire any time soon. If it is not in an automobile being used, it is not degrading. With the cap on it, there is nothing contaminating it. From what I was just reading, there is no practical expiration if kept in the original container.

share|improve this answer
1  
Ya beat me to this one, @Paulster2. Even mixed with distilled water, it really should last a very very long time unless something attacks it chemically. –  TDHofstetter Aug 22 at 0:46
    
I was seeing sources which said they used coolant over a decade old without issue. When you consider they can recycle this stuff over and over again (assume by cleaning), it will last for a very long time if left alone. –  Paulster2 Aug 22 at 1:11

When the word coolant is used in can mean a couple of things. Coolant made up of antifreeze and water out of your household tap, 50-50 solution, would last for around 3 years. Coolant made up of antifreeze and distilled (de-ionised) water, 50-50 solution, should last for around 5 years. Because of the nonsense surrounding 'coolants' always adhere to the instructions on the supply container. If you live in an area of the world subjected to very low temperatures you could look at a coolant change on the outset of winter as a sort of insurance. An antifreeze mixture should only be at a max of 50% as any greater amount of antifreeze will increase the freezing temperature. ie 50% antifreez would be -30C freezing, 60% antifreeze would be -20c.

share|improve this answer
    
What about 100% antifreeze? (I am asking about the remainder in a plastic jug, not the stuff I mixed and put in the car) –  user2813274 Aug 22 at 0:17
1  
In an air tight container it will last indefinitely. –  Allan Osborne Aug 22 at 18:55

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.