Best Buy and Crutchfield will let you know which speakers will fit in your car. For example Infinity 6x8's will fit in the rear deck of your Taurus.
The 2008 Ford Taurus has a V6 engine.
The 2008 Ford Taurus has a 3.5 L base engine size.
Front 6X8 Rear 6.5
BCI group size ( 59 ) Originally equipped with Motorcraft BXT-59 battery ( 2008 Ford Taurus )
6 1/2
According to the 2008 Ford Taurus X Owner Guide : It came from the factory with the ( Motorcraft BXT-59 battery ) * That's BCI group size 59
5 1/4"
The 2003 Ford Taurus has a V6 engine.
The 2012 Ford Taurus has a V6 engine.
The 2011 Ford Taurus has a V6 engine.
The 2004 Ford Taurus has a V6 engine.
The 2013 Ford Taurus has a V6 engine.