Want to know what happens to a live axle when jumping curbs??? Just watch ONE V8 SuperCar race from Australia, and you will see EVERY car jumping curbs. They are mandated a live axle, even though the chassis are originally built with IRS, and mandated to run a spool at all events.

When the cars jump the curbs, the wheels have liters of air under them. The effect is minimalized by the spool which delivers 100% power to the opposite (still in contact with the pavement) wheel.

Quite the lesson in drivetrain dynamics...

Jeff,

Sometimes the live axles "bend" in service and acquire some camber... I'm not sure the mechanisms are fully understood....

But the lack of camber and toe changes surely make the live axle a good choice if one can tolerate the expected unsprung weight.

Finally, I believe the lack of toe and camber change, in addition to the ability to harness the axle torque reaction, gives the live axle an advantage in traction out of the corners with especially high horsepower cars. The new generation Mustang is certainly competitive with the competition, all of which have IRS...and its corner exit is impressive. Only Porsche is better, and that probably is because of its greater rear weight percentage.

Bill