I kind of skimmed through this thread, saw the mention of the electric assist power steering found on modern cars. I personally have a love/hate relationship with them. On one hand, they do work very well, and are very easy to service should there be a need to replace the rack itself (no hydraulic lines to deal with, no need to bleed it after replacement). On the other hand, almost every single one I've dealt with is also tied into some sort of Vehicle Stability Management System, which also ties into the ABS as well. That can be a pain to get set right after aligning a vehicle, as there is a sensor in the steering column that needs reset. The sensor gauges how far the wheel is turned from center, not only telling the control module how far the vehicle is being turned, it also tell the assist system that it needs to kick in. While most of the time, this isn't an issue, if the sensor isn't reset after resetting the front toe, it can read the wheel as being "off center", even though it really isn't. What that will do is cause the power assist to kick in to attempt to "straighten" the car, as it gets a confused reading from comparing an "off center" or "turning" reading from the steering wheel, but getting a "going straight" reading from the ABS sensors at the wheels. As long as the sensor gets set correctly after a toe set, they system works fine.
On another note, I noticed a mention of it being primarily on smaller cars. The electric assist steering has been popping up on GM FWD full size cars recently (Impala), and for '15, it's going start seeing use in at least the 1/2 ton pickups and SUVs. I suppose it could be adapted to older vehicles, though it would require a stand alone control, and perhaps a
dumbed down" version of the steering angle sensor without the VSC system.
