First off, we need to know what mods are on your truck. It looks like you have the lift kit. Do you have 4wd installed.

When you start adding power to xmod trucks and putting it in high torque situation, the stock parts usually end up breaking. I have not seen a good stock off roading xmod.

For more power to go through grass, evo boards can handle 6 cells. Adding cells adds stress on all of the components remember. Also, you could buy the motor upgrade kit and increase the gear ratio giving the truck more torque with lower speed.