Hello Yesterday new summer tires in 235/45/17 97Y XL had to be raised. When I wanted to collect the tire data like DOT, production location etc. for my app for vehicle expenses after the assembly, I noticed that two of the tires were DOT4720, but two DOT4218. After a short discussion/telephone call from my workshop directly to his supplier, who runs a tyre trade/workshop himself and he changed the “old” for new ones and also without additional costs (The alternative would have been 30 CHF impact per tire. The problem is that I distribute my annual kilometers on 3 vehicles. To do this, then on a set of WR or SR, so that the tires become rather old/harden before they went down. That’s why tyres of newer production were more valuable to me than the price discount) The tyre dealer assured me with confidence that the tires are directly from the manufacturer and could not explain how it “old” from the manufacturer. He had ordered all of these, had no old stock in stock. He ordered and received directly from the manufacturer. Old wisdom, it doesn’t hurt to look at it himself…