[Tommy]

Here's the classical way of describing it for the non-technical. Imagine a four legged table on a flat floor with all four legs the exact same length. If the table weighs 40 pounds and the weight of the table is evenly distributed, the foot of each leg will be carrying 1/4th of the weight, or 10 pounds. Now imagine that you saw a quarter inch off the bottom of one leg. The table will rock back and forth between the short leg and the one opposite it, with most of the weight being carried by the other two legs. You might find, for example, that the short leg is carrying no weight, the one opposite it is carrying 8 pounds and the other two legs are carrying 16 pounds each.

If the distribution of weight in your car AND the suspension settings are not optimized, your tires may not be carrying equal weight. Thus, when near the limits of traction (e.g., hard acceleration, braking or cornering), a tire carrying lighter weight may break loose before another. This will happen sooner if the corner weights are not balanced, and it may cause the car to change direction (left or right spin).