Kerbin Large Rover Tipping

[Rugnir]

I have built a large manned rover in ksp to rescue downed pilots and it has been through various stages, however i have never been able to drive it more than a few km or kerbal before it tips over. so at first i think to myself: hmmm, need to make it wider. but no! even with masses of struts keeping it longer and wider than those orange tanks, when on full speed it just tips after a few km.

any ideas or help? i wanted to keep one side level with a docking port to allow multiple rover interfaces, but that should be ok for driving over the perfectly flat ground immediately surrounding ksc right?

[Panichio]

Images please. From the description, though, there might be something that is hitting the ground and causing your rover to tip over because of it.