The rear speakers are the same size of the front. 6.75" but 6.5" will work also
The door speakers in Geo Prizms From 1993-1997 and possibly newer are 4in. and the rear speakers are 6.5in.
30
Rear deck speakers are 6" or 6 1/2" and the door speakers are 4"
my 1990 has 4" speakers hole in the back but i have 5" speakers in there now.
Begin by removing the covers to your 1993 Geo rear speakers. Remove the speaker retaining screws. Remove the wiring harness from the back of the rear speakers. Reverse the process to install the new rear speakers.
The door speakers in a 1996 GEO typically measure 4 inches in diameter. However, speaker sizes can vary depending on the specific model and trim level. It's always a good idea to verify the measurements or consult the vehicle's manual for the most accurate information.
6.5 inches
6 ¾". Standard 6½" speakers can be made to fit by drilling the mounting ring, but it would be best if purchasing new speakers, to buy ones that already have an adapter ring included or are already designed to fit 6¾". Also, because the speakers are mounted low in the door, choosing ones with a pivoting tweeter would be wise.
4" in the dash, and 5" in the rear deck if it's a sedan, or 5"x7" if it's a hatchback. Hope this helps.
6.5 in the back
The 1991 Geo Metro typically comes with 4-inch speakers in the front doors and rear. Depending on the trim level and options, the vehicle may also accommodate larger aftermarket speakers. For optimal sound quality, many owners choose to upgrade to slightly larger speakers while ensuring they fit within the existing mounting locations.
The front speakers are 4.75" (yes, a non-standard size) and the rears are 7.0" (you guessed it, another non-standard size). 4.5" aftermarket speakers will fit the front with some additional foam baffling round them to make them air-tight and 5.25" and 6.5" speakers will fit the rear with a Scosche adapter bracket. I have 6.5 inch Pioneer speakers in back. I just screwed the new speakers in the stock mounts and it worked fine.