Bottom line is something went wrong during the 1.11 update and no one knows what it is including rock-star nor do they really care sitting on a giant heap of money ignoring the various different players experiencing Freezes since 1.11
i have tried every possible fix and none of them work, last time i'm gonna say this not your ps3 its the update,
"HOWERVER"i found a way that i can still make loads of money online while avoiding all open session lobby's
First thing you need to do is go into story mode then make an invite only session from there you can go to the start menu, jobs, rock-star created i always pick roof top rumble for the highest payout. But the cool thing about invite only session is when you leave the job and go back into free roam it puts you back into your own invite only free roam session, right now this is the only way i can play gta 5 online without freezes which leaves me to believe that it might be other peoples connections or items freezing other people in the session.
i have made almost a mill in the last week using this method, trying to save up for the new cars/houses coming out in the next update hopefully they fix the freezing issue to, if not looks like ill be doing allot more invite only sessions.
This is not a fix, just a way to "Avoid" the constant freezes if your experiencing them.