Crabbing

you can NOT tell a car is crabbing by following--unless it is really really REALLY bad and you would likely notice driving it. IT MIGHT BE an optical illusion

In my 20's when in the Navy, San Diego, a friend had a brand new Chev K20, raised 8, big tires, and ran spacers on the front for the tie rod ends. The front and rear track were different width, and you would SWEAR that it "crabbed" while following. But it didn't. It was straight as an arrow

YOU MUST measure the whole thing "for square" (by several means) to determine