I seem to remember installing 3 discs on my 360, but might have been 2. Regardless, the game was huge on last gen, 15.5 GB, and that was before GTA Online was added. GTA V had one of the biggest installs of any 7th gen game, there were only a handful of 3 disc games like Final Fantasy 13 which were larger, and GTA V ended up passing them all after GTA Online hit. It was so big that it wouldn't fit on a launch model 20 GB Xbox 360 after GTA Online hit.
I looked it up, and it's 2 disks. Apparently the player never needed to swap disks ( good thing, that would totally ruin a game like GTA V. lol ) just install the first disk and play off the second. Actually, that 15.5gb file size range was quite common on the PS3 as far as first and third party exclusives were concerned. The 3 PS3 Yakuza games were all around the 20gb mark for example.
-Just for fun, I looked up the file sizes for FF XIII. 18gb on the 360 and 38gb on the PS3. I'm quite sure that was due in large part to the usage of blu-ray quality cutscenes in the PS3 version.Last edited by COKTOE - on 27 September 2018
Chinese food for breakfast