These are Lincoln Town Cars, a model recently dropped after many years in production. The upper photo is of a 2002 model, the lower shows a Town Car from around 2011. Their shield-like grille shape dates from the 1993 Lincoln Mark VIII, though rectangular grilles with wide chrome frames and thin, vertical bars continued on some models until the 2002 model year.
Changes in grille design rapidly accelerated by 2007 as Lincoln sales continued to dwindle from the 1989-90 peak. 2013 models have faces such as on the new MKZ model shown here.
I don't like this latest grille design. But I do find it interesting how Lincolns stylists raided the marque's historical parts bin, so to speak, in a search for a different theme from of 1993-2007 and the 20-odd years before that.
Consider the Lincoln Navigator SUV (sport-utility vehicle). The upper photo is of a 2003 model, the lower one shows the 2007 Navigator with a different grille theme. Where might that theme have come from?
Probably from the design Lincolns sported for the 1946-1948 model years. Shown here is a Lincoln Continental Cabriolet.
Then there is the grille on the 2013 Lincoln MKX crossover SUV. It has been around for a few model years and is similar in spirit to the MKZ shown above except that the grille bars are heavy and are aligned vertically rather than horizontally. And where might this have come from?
Once source was probably this 1995 concept car called the Sentinel. But we can push the idea even farther back to...
...the 1939-1941 model Lincoln Zephyrs and Continentals (above is a 1941 model Continental).
In the midst of this stylistic thrashing about, he find the...
...2007 Lincoln MKX (upper) whose grille reminds one of the of the 1964 Lincoln Continental (lower photo).
Where else might Lincoln stylist care to dig for traditionally based grille themes? I suggest these as starters:
The upper image is of a 1942 Lincoln Continental Cabriolet, the lower shows the grille used on 1949 Lincolns.