If you drive slowly (not more then 10kph) with tanks they often stutter.
The reason for this is because they have fake gears to help "fix" the engine not able to rev up. This workaround causes the gearbox to constantly change gears at slow speeds (infantry support, walking speed) as those gears have extremely high gear ratio and therefore are very short.
The workaround does not fix the problem entirely and introduces this problem. (see http://feedback.arma3.com/view.php?id=19183)