Why did my axle break?

[M2M]

Originally Posted by Bob Bidonde

Axle failures like yours are not rare occurrences. This type of failure is the result of fatigue and a stress riser. The photo here is a textbook classic of how a fatigue crack initiates at a stress riser and grows to become a static overload.

The stress riser is at the end of the axle's key slot where the taper begins. Note how the crack grew outward across the section of the axle.

Would not having rear shocks on a car mean more fatigue and a stress on the axles?