Cadillac's on-again, off-again plan to replace the aging DTS and STS with one flagship product – which may or may not be known as the XTS – is reportedly back on track. According to Motor Trend, the original plan to use the Zeta platform of the Holden Commodore and Pontiac G8 has been shelved in favor a stretched version of Cadillac's own Sigma chassis that underpins the smaller CTS. If there's any truth to these rumors, we should expect to see the new Caddy for the 2012 model year.

The demise of the DTS also spells impending doom for the Buick Lucerne since the two vehicles are built atop the same platform at the Detroit Hamtramck assembly plant. MT reports that Buick will get two new models to replace the Lucerne, one of which may revive the old Invicta name from the 1960s. That mid-size sedan would replace the canceled Saturn Aura and be based on the Opel Insignia, which uses the same Epsilon II platform that's used by the 2010 Buick LaCrosse.

The second new Buick will reportedly be a notch smaller and will share its compact Delta guts with the Chevrolet Cruze but be fitted with the suspension adjustments pioneered on the Opel Astra. We'll just have to wait and see how that car goes along with Fritz Henderson's proclamation that he's 'not a fan of rebadging' if it ever sees the light of day.

[Source: Motor Trend]