Improper engine break in.

We had a very hard time making a set of gears last in our race truck. The only way we found to get them to last longer than one race was to break em in. Extreme example sure, 5500 pounds, 37” tires, almost 700 hp, 400-1000 mile races, but it really extended the life of a gearset. We can now get 2 races out of them. Lol