Greetings from LS forum.

Does anybody know about how the factory warranty works on the Deville? I am looking to purchase an used 04 DTS and according to the CarFax it should still have 6 months left on the factory warranty. Does anybody know if this warranty would transfer to me or have any experience with this? Also, does anybody know any red flags or typical problems with this vehicle or should the factory warranty handle anything that may come up?

The original bumper-to-bumper warranty stays with the car. So does a GM "Major Guard" warranty. You might look into the possibility of "extending" the warranty through Cadillac. If it is not a "certified car" which already has an extended warranty, you might be able to do so.

Believe original GM warranty on Cad was 48 mo/ 50,000 mi whichever comes first; but auto may also have an extended warranty which if GM may be as long as 8 yrs/ 100,000 mi or??
Also, suggest checking VIN with GM to find if it may have "original", "GM extended", or it be a "GM Dealer Certified" which may have TBD???
If a third party extended warranty, who knows; but you would likely need to read the written policy for transfer terms.
Good luck