5:181 is now 5:385 in the newer lifts.
In my manual 5:181 is" Signal from steer angle transducer is 180 degrees incorrect"
I had this problem ( read above) and it ended up that the radial bearing was worn badly, and chewing the end off the steer angle sensor.
In a nutshell check your steer angle sensor for damage. Like someone took sandpaper to the sensing surface. It's hard to see but... also check the wiring to it.
If your machine is at the 12,000 hour area - you may have final drive issues.ie: worn radial bearing.