[OXO cube]

hi guys 
i have a scalextric cadillac LMP car C2259
this car has independent front wheels on stub axles 
   
these wheels feel very loose in the axle mounts 
and im worried that when running this car , the front wheels will bounce around and effect the car stability etc
has any1 changed this setup to a solid axle ?
did it make any difference ?
do the wheels just twist off the same as the knurled solid axles ?

i have tried to check on the net , but i must not be using the correct search words 
any help would be greatly appreciated 

kev