I'll preface this with I did a pretty hefty search for a solution, and I couldn't find anything. So, I'm making a post.
I'm having an issue where I go to either spawn a vehicle or select it from the LSPDFR vehicle selection menu when you go on duty. The problem itself is with the extras of the vehicle. If I add the lightbar it will show up for maybe 0.5 of a second and then disappear. If I try and add the pushbar it will do the same. It doesn't matter what extra I try and add to the vehicle I get the same result. Anybody have any idea?