the car fall when i restart 3ds max

[memo92]

please help me guys, ihave a problem in the craft animation that after doing my work in any kides of cars ( 2WE , 4WE ) and save it when i come back to it ( open the max file ) and i start recording, the car fall as afree fall i do the best to know where is the problem but ididnt know (( the problem is not in the gravity ))

[Patrik Martin]

Try to uncheck the "Use Fast Ray Cast" from the "Ray Cast Properties" in the 4-Wheelers configuration.