What's the definition of a new tire? Sale date? Manufactured date? ?

 I recently saw a car I sold a few years ago with tires I had bought about a year before the sale. The owner told me they were going to have to get some new tires, but only on the back because of some cracking on the tires. I thought it was odd that only two of them were doing that so I checked the manufactured date. Two of them were made in 2019 while two of them were made in 2016. The two 2016 tires were the ones needing replaced. 

So what's up with that? Do I have to check every time I get "new" tires now for the manufactured date and/or have to specify only recently made tires? Is this a common thing all tire stores do? Just doesn't seem right somehow...

Always check the date, you'd be surprised what is sold as "new" tires, and rubber does not like age.

yeah, I bought new tires for Carli's car from Discount Tire Direct in 2020 and after I mounted them I noticed they were mid 2017 dates. They were like "climate controlled warehouse, still count as new, not returnable once mounted" and now of course, maybe 5k miles later they are starting to crack. Extremely not happy and next time there will be date codes checked before any mounting happens.

Tire Rack talks about this topic here: How Does Age Affect Tires?

One answer provided in that article:

Tire manufacturers' replacement tire warranties begin when the tires are purchased and typically last 4 to 6 years from that date. This allows the tire manufacturers' limited warranty to accommodate the time it takes tires to be shipped from the manufacturing plant to the warehouse or distribution center, to the retailer and to the consumer, as well as the time they spend in-service on the vehicle.

I got some tires from simple tire.com that were 7 years old when they arrived. They went straight back and I reordered from Tire Rack. You definitely need to check the manufacturing date. 

Keith Tanner said:

I got some tires from simple tire.com that were 7 years old when they arrived. They went straight back and I reordered from Tire Rack. You definitely need to check the manufacturing date. 

I returned a set from Discount Tire that was just short of four years old for the oldest tires to about two and a half years old for two newer ones.

They exchanged them for a matched set, less than five months old. They were for my wife's van. 
 

TR sold me a set of Rivals for the Miata in 2021 that had a 2019 build date. I called, was told that the factory was closed during 2020 due to the pandemic. I heat cycled them and racked them for a week, but I didn't think they performed like new tires for as long. 
 

Here's my "old tire' story as of recent....  

For my fleet Prius I have bought no less than 5 sets of Falken 201's over the years and my retailer of choice was TireBuyer.  When I was first buying these tires they were like $62 per tire but had a 65K treadwear.  The tires came with 2 yr road hazard included.  

Sept 30, 2021:  I get an unrepairable puncture and begin a claim for road hazard.  Keep in mind that I buy another tire almost immediately because it becomes evident that the "claim" will take some time. 

Dec 31, 2021 (3 months later) I get notice that they have approved my claim.  I could have $68 cash or a replacement tire.  By then the tires are $82 each so I agree to the replacement tire.  I figure I'll need a tire in the fleet sometime anyway.  

Jan, 19, 2022 (20 days later) I get informed that the tire is shipping.  In code date this would then be about 03-22 (3rd week of '22)

The tire arrives and it is manufacture dated 18-21 or roughly 37 weeks old or about 9 months old.  I think to myself, "the free ones most come from the old pile, but, its free and I'm okay with that."  

Fast forward to about a month ago on April 29, 2023 (or 17-23) I order 3 Falkens, since I already have one tire that has been sitting here for more than a year now.  I order the 3 tires via Walmart which gets their tires for American Tire Distributors(ADT) and the website TireBuyer is the consumer arm of ADT.  I take this to be that the tires then ultimately come from the same source.  These 3 tires arrive and two are dated 44-21 and one is dated 48-21.  

These tires that arrive are roughly 73 weeks old or nearly 1.5 years old.  The one tire I have already is about 100 weeks old or nearly 2 years.  

But, I went ahead and had all 4 mounted.   I had figured that I would have one tire on the car that was nearly 2 years old (which was the free replacement that sat in my garage) and 3 tires much newer.  As it turns out all the tires on my car were manufactured in the same year...ha.  

My other logic is a suspicion that Falken (or at least ATD's inventory) has not been added to since 2021 for this model/size.  It is admittedly probably not the most popular model but I have had a good track record with the many sets I have owned.   

date manufactured and treatment since then is what matters

In reply to Toebra :

That's what I'm hoping on. I bought new wheels and tires in 2019 (tires also dated that year) for a big brake conversion that got sidetracked waiting for parts, test fitting, laziness, etc. They've been stored in black trash bags indoors, not a garage, but my guestroom.