Find which vehicle it is based off of in real life and/or show us an image of the issue like the ticket regarding the exhaust from the AH-99 has.

i dont use real life as refference, but the textures/model in the game, the Marshall and the IFV uses the right exhaust but they have the same texture for an exhaust in the left side

Due to the Marshal having mirrored UV's for its sides.

so, in real life they have 1 exhaust but in-game model uses a mirrored texture?

Could you provide an image of the issue from in game.

http://i386.photobucket.com/albums/oo303/prion_photos/P1020110.jpg

http://media.militaryphotos.net/photos/albums/bokwa/aak.sized.jpg

i am unable to provide a pic, you have to use the marshall (so far, i was wrong with the blufor IFV, it does have a texture of an exhaust for 1 side, and its where the exhaust work) and look closely to the right and left side and check how both sides have the exhaust holes but just the right side one works

There, after some time of research i pinpointed the vehicles, just tested with ground ones, didn't tested with quads and civilian ones