So… This happened when I tried to accelerate my vehicle.
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I found a way to stop the bug though: If a go in reverse (where it still does this.) and get back to the controls and stop the vehicle, it drives as normal. It actually happened to me before. In both cases the vehicle was facing the same direction and it happened after a long period of crafting.
On a completely unrelated note, it is possible to craft a quad smg turret with just 1 smg (Assuming you have the other materials needed)
[size=3pt]I shamelessly exploited this.[/size]