wheel speed sensor problems
 

I have an 02 LS with 87,000 miles now. two years ago at about 65,000 miles I had to replace the right front hub to cure the trac alarm abs warning that kept coming on. no problems until about three months ago I started having trac light come on on a slow right hand turn and sometimes the brakes would almost fail on slow speed stops. then it became a full time problem. did a scan and the right front wheel speed sensor would read zero until about 15 mph and then would match the other 3 wheels but would always trip the system alarm first. another new hub and no problems for 2 weeks. then constant alarms every time I drove it. I then repalced the right side wire harness and and no alarms for 2 weeks again. as soon as I thought I had it fixed it now goes off all the time. every scan says right front what the heck is wrong here. sorry for the long post but I need some ideas.