2002 Cadillac DTS Bad Rod in Engine

I would guess that 2000 to 2004 would fit. I would use the same VIN, which for a DTS is probably a 9, but it could be a Y. There may be some subtle differences. You might be able to contact a GM parts source, and get a range of what years the P/N engine fits. The parts catalog will not tell you what the differences may be in why one won't fit. Say if by application, the part number of engine for your vehicle only has a range of 2002 DTS, it will not say why a 2002 STS won't fit. Alot of changes those engines have encountered over the years are structural, having to accomodate different mountings, and ignition system changes.