Rear Deck Speakers Are 6x9" and the front door panel speakers are 5 1/4"
6x8
Which ones?
4x6
I believe they are 8" by 9"
Should be 4x6. 3x5 is the other size.
front 6x8 back 6x9
fronts 5" x 7", backs 6" x 9"
The front speakers in a 1997 Mercury Grand Marquis measure 6 inches by 8 inches and they are located in the front door. The rear speakers measure 6 x 9 inches and are located in the rear deck.
Crutchfield.com states that you can use up to 6"x8" in front doors and the same for rear deck.
15 inch
According to the 1998 Mercury Grand Marquis Owner Guide : ( 71.9 litres / 19.0 U.S. gallons )
Answer The front door speakers are 4x6 inch and the rear deck speakers are 6x9 inch in a 2004 Grand Am.