DOT code is kinda like a VIN number for the tires. All you really need be concerned with are the last 3, or 4 numbers...

Last 3 numbers 099 - that tire was made in the 9th week of 1999.
Last 4 numbers - 0901 - that tire was made in the 9th week of 2001.

Six years is a safe recommendation but climate plays a large role as well. Since I've been here in Texas, I've seen 3 year old tires cracked severely. Heat is the enemy to tires. Low inflation makes them run hotter. Years back when I worked for Goodyear and the run-flats were introduced as standard equipment on the 97 Vette, they actually ran New York to LA with a Vette on a deflated F1-GS EMT, re-inflated it and tracked the car with no issues but since the Vonage commercials so aptly put it: People do stupid things, they're rated for 50 miles at 55 mph during any "deflated" or flat occurrence.

A side note. In 98-99, can't remember which, I did the Skip Barber 3 day course at Pocono Raceway while Goodyear was still sponsoring them. We ran 2 Neon's with 3 Goodyear Eagle HP's and a run-flat on the left front. Don't remember the model but it was basically the old Eagle Aqua-Tred tread pattern in run-flat construction. We were split into 2 teams of 11 guys. Each one of us ran 2 auto-cross laps - 44 laps total , with the EMT tire deflated. Other than a little rumble during the hard turns, you'd have been hard-pressed to even know the tire was flat. Those little "nipples" didn't even wear off the shoulders. Great technology but they're a PITA to mount on the wheel and ride hard.

__________________
Sharing my partner's 2012 Forte 5dr SX til I find my next 123 or 126..
-
Do I miss being a service advisor ???