All the players of GTA 5 who have been trying to transfer their cars, either modded or not, from the single player to GTA Online, there is a new glitch in the game which lets you do just that.
The step by step method is as below:
First of all, spawn location must be set to “Last Location,” and you should have no personal vehicles outside on the streets (all of them must be in your garage).
Go to the nearest Los Santos Customs and just stand outside. Then pause the game, go to “Online” and select “Leave GTA Online.”
You will spawn in the story mode. Now you need to find the vehicle you want. If you want to mod the vehicle, switch to Franklin first and then once you have the vehicle you want, modify it at his Los Santos Customs at Sandy Shores.
Now, jump out of the vehicle and stand next to it, then press pause and start an invite-only session of GTA Online.
Then you will spawn in GTA Online and should be across from the Los Santos Customs. Now find the nearest car (any) and take it inside the LSC. When inside, press pause and go the game store for your system.
Now is the important part: as the camera zooms out above the city, if you are on PS3, then press the PS button on your controller, go to PSN and press triangle over “Account Management.” Sign out. If you are on Xbox 360, when the camera zooms out you need to unplug your network cable from your console.
Either of the above methods will result in an error when your game store loads up, and you will automatically go back into single player mode.
When you’re back in SP mode go back to the car you want to take over to GTA Online and take that to the nearest LSC. Drive up to the door of the LSC and when it opens park it halfway through (so that it can’t close).
Now stay in your car, and if you’re on PS3 sign back into PSN (and if on Xbox 360 plug your cable back in and sign in). Then press pause and start an invite-only session of GTA Online.
You’ll spawn in GTA Online and be near the LSC. Go to the LSC’s door and you should find your car from story mode there parked under the door.
This is the guide for getting your awesome single player cars in GTA Online. Does this help you? Let us know in your comments!