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Coolant reading


So, I checked the coolant level today on my 2017 MazdaCX-5. While doing so, I noticed that the coolant level was on the “L” however, my radiator was completely full. The engine was cold when I checked. Is this normal? Do I need to buy coolant and fill it to the full line when the engine is cold?

The vehicle has 2,590 miles on it, so I don’t suspect a leak, and I don’t see any coolant on the ground. The dealer is 45 min away, so I was thinking I would just buy coolant and fill it, but I don’t want to overfill. The dealer did that with my last Acura, and I had coolant coming out of the resovoir because there was too much.



Image taken from the owners manual

It may well be normal. Fluids contract when they get cold… and much of the country right now is in a “arctic” weather pattern. It’s about -1F at my house as I write this.
Just get the proper coolant, add a bit to the reservoir, and monitor the level for a while. Post the results.

+1, but it is important to stress the word “proper”.
The OP should consult his Owner’s Manual for the details, or if the info in the manual is unclear, a call to the parts department at the dealership should yield the necessary info.

I don’t think any action is needed

If the coolant level is at the “L” mark cold, then it’s still fine

Odds are, if op were to drive the car 20 miles and check again, for example, it would be nearly to the “F” mark

I usually buy a gallon of coolant at the dealer along with the touch up paint, and any other potential special fluids needed when I buy a car. Usually don’t have to add more than a cup or two a year though. Just good to have it on hand.

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The owner’s manual is the ultimate judge for your vehicle of course. The coolant level is at the “L” mark on both of my vehicles, prior to starting the car in the morning, especially in cold weather. I don’t want it filled much higher than that cold b/c when the engine heats up it might overflow the reservoir bottle and make a mess.