I would not call being unfamiliar with the warranty your vehicle came with as luck.
One the other hand, the part about getting it repaired before the coverage runs out next month can definitely be considered good luck.
Crossfire powertrain warranty terms have changed several times. The warranty manual that came with the car, the build date, and the in-service date are all important in determination of coverage.
1. 2004 model year Crossfires built (see decal on driver side door frame) before 10/01/2003 came with 7/70 powertrain warranty that transfers automatically to any number of subsequent owners during period of coverage at no cost.
2. 2004 model year Crossfires built on or after 10/01/2003 have 7/70 warranty that transfers to a second owner only (third or subsequent owners not covered) for a transfer cost of $150 that must be applied for at a Chrysler dealership w/in 30 days of purchase.
3. 2005 Crossfires have the same coverage as #2 above.
4. 2006 Crossfires only had a Basic 3/36 warranty, i.e. no additional Powertrain coverage. However, those that were sold on/after 07/26/2007 came with the Lifetime Powertrain Warranty which is not transferable.
5. 2007 Crossfires were the same as #4 above.
6. 2008 Crossfires also had the same coverage as #4 above though obviously just about any 2008 Crossfire would have been sold with the Lifetime warranty.