If you are talking about the speakers on either side of the back seat, they are probably 6x9. The ones in the door are probably 6.5" or a little larger. To know for sure you will have to remove the door panel or rear seat side panels.

AEM CAI, AFX Underdrive Pulley, Greddy Header, Tsudo N1 2.5 stainless catback, Homemade groundwire kit
17" Fondmetal 6500, Tokico Illuminas, Eibach Pro Kit Springs, Front Upper Strut Bar, Baer Track System, Drum to Disc, RMDSM Anti-sway bars front and rear.