Locking Differential Usage?

[otto burleson]

On this board, reference has been made to a "driver controlled locking differential." Is this a standard item? How do you engage the locking feature? I do not have any identified control.

[TechTalk]

A driver activated locking differential has been standard on Newell coaches for many years, as best I recall, since the late 1980s. When a coach is so equipped, a switch labeled "DIFF LOCK" is located on the instrument panel. In situations such as driving on ice, snow, or mud where traction becomes a problem, activating the differential lock prevents one set of rear duals from freely spinning while the opposing set simply sits inert. On three axle coaches, traction can be further enhanced by pushing the "TAG AXLE" switch to the down position, lowering air pressure in the tag axle air bags which transfers weight to the drive axle. As far as we know, Newell is the only motor coach manufacturer to include a locking differential, although we believe that this is a very worthwhile feature considering the less than ideal driving conditions that can be encountered on occasion.