3DS Max exporting problems

Ok Ive tried exporting a model from 3ds Max 7 to an X-File for a game Im making for University.

The problem is the 2 wheels go off where they like with the standard exported, and with the Panda exported, it doesnt display the wheels.

This is a pic

I hope someone can help me out, Ive tried grouping, collapsing, everything I know!

Cheers