I agree,. it’s most likely a lighting issue,. what’s your lighting setup?
Try making everything else invisible, then render the ground plane,.. (is it just a plane) or something else ?
If it shows up fine, then make each object visible again, (one at a time) and spot render each time to see what’s causing the issue.
If you make an image to use as a 360 background,. and fill the bottom half with the “road surface”, then it should reflect n the vehicle
hopefully you can see in this quick example, that the ground is reflection in the chrome of the fender / bumper,.. and the wheels
Click thumbnail to see full-size image