Many Tanks don't drive straight at low speed. The direction they are steering in is random. The magnitude differentiates between Tanks, the worst so far is the Panther APC and the Bobcat.
(Just to clarify - no i dont have any controllers connected that could cause this)
I noticed this problem as i copied the physx part of the Panther to my custom tank, which did drive straight before.
After i commented out the
line in the Physx part of the Config for the wheels, it drove straight again.
Therefore something must be faulty with the friction thing that causes this very noticeable Side-effect.