Axle Wrap

 When braking or acceleration forces are applied to the wheels, the resulting torque on the axle can cause the springs to deform (as on the left where the springs look like they're made out of a wet noodle). This is called axle wrap.

As your Toyota is modified: lift is increased, springs are softer for more flex, tire size and traction are increased. Axle wrap also increases.

On my Toyota truck I have 33 inch tires, soft crappy springs of an un-known brand (I should mention soft enough for axle wrap but not soft enough for a smooth ride), and a Lincoln locker in the rear. I didn't really notice axle wrap until I was spotting my wife over an obstacle and the back started hopping and kicked sideways due to the spring deformation.

There are many different views on different way to eliminate Toyota axle wrap. Here is a good write-up that discusses different type of traction bars and location points.

www.4x4wire.com/jeep/tech/susp/axlewrap/

Most people seem to agree that the ladder bar provides the best anti-wrap protection. If the lower arm is built low enough, it can also provide a significant amount of driveshaft protection. Here's a ladder bar built and installed on a Toyota axle:

http://www.yotatech.com/f88/traction-bar-fab-122658/

This winter I plan on building one of these for my Toyota. I will be sure to document the process so I can post it here.