The people who built the car were some of the best mechanical engineers in the automotive world, and then they tested the cars, more than almost any other company in the world. So when they give a spec for toe in, IMHO it is best to listen to them as they have the data and testing to back up their decision.

This / \ <--- is tow in, if the motion of the car is upward and the slashes are the wheels

This \ / <--- is toe out, if the motion of the car is upward

The reason to add some toe in is that the forward motion will tend to push the wheels rearward, flexing the steering linkage as well as taking up any play, and theoretical tow will achieve zero. If a brand new car requires some toe in (as per the specs), then one with some wear will need more toe in. An IR heat gun pointed at the tread can often indicate how the tire is tracking, hotter to outside = toe in, hotter to inside = toe out. Equal temp across the face of the tread would be optimal, what were looking for.

As stated, centering the steering is PARAMOUNT to the start of the alignment process.

But there is another part of this process to consider. As each front wheel is individually and independently adjustable, each wheel can thus be "pointed" in any direction, without respect to the centered steering gear, or the other wheels setting.

To get both front wheels correct, and to keep the steering gear centered, you must reference each wheel to the centerline of the car. IOW, you must simultaneously correct toe, while keeping the steering gear centered, while also referencing that both wheels are aligned to the vehicles centerline. If you fail to reference the centerline, you can have proper toe, yet still have both front wheels turned slightly left or right, and your steering wheel will be turned going straight ahead.


To achieve the greatest perfection, every bit as good as ANY alignment shop, you can simply run strings down both sides of the car, making them parallel to the cars centerline and outboard a short distance, 6 inches per se, and at a height even with the wheel centers. Now you can measure between the string and the wheels rim edge and simply need to equalize everything. With strings set up properly you can also check rear toe, though its generally not adjustable.

Four jack stands, two pairs, each pair with a long wood stick across them set one set to the front, and one to the rear. Tie strings equal and accurate distance apart on both sticks, and move each of them right or left as needed to bring them parallel to the cars centerline while keeping the strings taut.