How to mod correctly

I was thinking of modifying the small trailer and making it wider/longer, But my problem is this is my first time doing this stuff. Do i need to backup my game? How do i make a new trailer slot? How would i modify it? etc

 

The wiki is your friend.

 

Just so you know, the small trailer is in the common.zip, so it can be used by any vehicle that has the correct slottype. You won't need to back up the common.zip or anything else, as you shouldn't modify it. In the common.zip, the small trailer's files all have the prefix tsfb (stands for trailer small flat bed). Your's should use a different prefix (tlfb with the l for large, for example). Copy those, rename them, and edit as you wish. While you work on your mod, have the files in Documents\BeamNG.drive\mods\vehicles\common. Everything else you'll need to know is in the wiki.

 

Is there a way i can copy all the wheel files and crap and just modify the length of the bed and position of the wheels, in blender or sketch up? Or do i have to change all that? Because if i do, I am going to cancel, as i have no clue how to do it, even when i read the wiki.
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How do i import into blender? I have searched everywhere and can not figure out how.

 

File>Import>Collada then find your file.

 

Will try. Thanks.