DoToH

After doing as people above said, take a while to test your rover on kerbin surface... drive it fast and make some sharp turns. Keep in mind that any stability problem on kerbin will go worse and show up at slower speed in a low gravity environment. And, if your rover has any SAS module or pod with some torque force, switch to docking mode to drive it.

Try this one And tell me if it works like you want to. Edit: forgot to link the two side 2,5 m sections to the center one.... you'll get the the idea.

Maybe this thread can give you more info about your issues.