1st of all, welcome to the forum.
Bummer on the blowout, if that is what happened. If you heard the pop, then is was probably a blowout. If you didn't hear anything, then the tire could have lost pressure gradually, and you not realize it was flat until the tire started to shred.
If those are the original tires on a 2004, then you need to replace all of the tires....they were long overdue several years ago.
There should be a date stamp at the end of the DOT code......ie something like 2603......that would be the 26th week of 2003 is when the tires were manufactured.
Here is an example: http://www.tirerack.com/tires/tirete....jsp?techid=11
You may have to look on the back side of the tire for the date code.
Chap , DW Joy, and Fur Baby Sango
2006 Ford F150 Super Cab 4x4
2008 Surveyor 263