Hi , i have install the Jumbo kong tires /ofna pirate rims on the genesis , when i lift the truck up the , the wheels seem to slide uncontrollablly towards the side that i tilt , that when the power is off, is it normal ??

and when i push the truck turning right/left , the wheels seem to be wobbly and not firm ??

How shall i improve on it and can i change the steering servo to a more power ful steering like Hitec 645 ?

Thanks