Assuming a collision, a question remains as to whether the collision was the proximate cause of the burned-out transmission.  In this case, it is easy to see that the damage to the transmission was not a natural result of colliding with the ditch. When the car came to rest in the ditch, the insured could have chosen to leave it there and call a tow truck. If he had done so, the damage to the transmission would have been avoided. His decision to rock the car caused the damage independently of any collision.

The next consideration is whether the transmission damage might be covered under the other than collision coverage of the personal auto policy. This covers any physical damage to the auto that is not defined as collision and that is not excluded.

An exclusion that might be thought to apply is the wear and tear and mechanical breakdown exclusion. This exclusion does not apply, however, because it is designed to exclude coverage for gradual damage to the auto that occurs under normal and expected conditions. It is well accepted that if the insured, while changing the oil in his car, forgets to replace the old oil and drives the car in that condition, there is coverage for the resulting "mechanical breakdown or failure" of the engine. Burning out a transmission by trying to rock a car out of a ditch is a similar unusual breakdown resulting from an insured's mistake.

The final consideration is whether this loss was "accidental," a requirement found in the physical damage insuring agreement of the personal auto policy. The policy is not designed to cover intentional damage to the automobile. While it cannot be denied that the insured purposely rocked the car back and forth, his intention was to get it out of the ditch, not to damage the car.

For these reasons, the insured may recover under the other than collision coverage of the personal auto policy.