A few weeks ago, the right-front wheel bearing assembly on my 2001 Blazer began howling at highway speeds. In the last week or so the 4-Lo Indicator Light began flashing intermittently (at varying speeds) and, after 30 seconds or so, the flashing would stop and restart (sometimes in as little as 5 seconds or as long as 2 hours). From what I understand, the transfer case actuator requires a series of events to occur before the axles and hubs would actually engage (i.e. vehicle must be stopped or reduced to low speed and the transmission be in Park or Neutral) so I wasn't too concerned about the problem. However, I did find myself in a situation where the 4-Lo Light began flashing (on it's own) immediately following ignition and, before I realized it, the light went solid indicating 4-Lo was engaged. I was able to disengage the front axles and hubs only after continually pressing 2-Hi.
I've since replaced the front wheel bearing and assumed the problem 4-Lo problem was associated with the worn bearing (my assumption being based on the fact that the bearing/hub assembly utilizes a speed sensor and for no other reason). Well.. the light began flashing again...
Does anyone have any thoughts and/or answers? I would appreciate any insight. Thanks!