Truck keeps popping into 4x4 on its own

[95GTS]

Does your truck have the electronic shift on the fly button/switch or is it the lever on the floor? I'm assuming your hubs are the autolocking. What does it do when it "engages"? It doesn't make any sense. Even if the hub is locked as long as the 4 high or low isn't engaged it shouldn't affect anything. It wouldn't pull unless the 4 wheel drive was engaged. The reason I was asking if it was electric push button was maybe the 4 wheel drive is kicking on for some reason which will then cause the auto hubs to engage into 4 wheel drive. Usually when a hub goes bad you don't get your 4 wheel drive when you try to engage it.