Hi pantiger man,
The drive sprocket and return wheel screws are almost always loose on new HL tanks (more so on the left side for some reason). Also check the sprockets, road wheels, and treads for left over flashing etc. This is a good time to check that the track/treads are free and not binding. It is a good idea to break the motors and tracks in by running it at the slowest speed while up on "blocks" for a couple of battery cycles. Doing this will, of course, also cycle the battery at the same time. A slow speed break in can improve the elect. mtr brush contact which will improve power and help the tank "track" or drive in a straight line. High speeds and or loads during motor/brush break in can cause pitting in the brushes as well as unequal brush contact between the two motors. This will cause the tank to always steer a little to the left or right as will track/tread binding on one side or the other.
These tanks also have a gap or open space on each side of the hull just above the drive sprokets that can allow excessive dirt, sand, water, etc. into the hull. The good thing is that these holes are easy to cover with duct tape without disassembly of the hull.