Hi there.

I have an Isuzu KB300 Auto 2x4. My diff locks automatically when I drive. I would be doing 90km on the highway and then boom, all of the sudden the light on the dash goes on and the diff is active. I immediately slow down and try to take the corners as wide as I can to minimize my problem. It seems like when the pickup is cold I dont have this problem. As soon as I have done about 20km it happens. Only the past couple of days. The Diff lock button on the dash itself stays off.

Any idea what it could be?