These codes are not difficult to read. They are difficult to find.
I have an Infiniti and a Nissan pickup. For each vehicle, the spare is a different make from the road tires, so I have 4 different makes of tires.
I just went out to check the dates, and in every case the date is on the inside of the tire, which makes it very difficult to see.

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This is the spare of my Infiniti. It was made in week 37, so, September of 2015. Four year old tire, not bad for a spare.
They have been using the same code for at least the past 8 years. Obviously it is federally mandated because the numbers are all the same size, about 3/8 inch high.


My pickup spare tire, I just bought this one two months ago, manufactured January of this year.

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