I don't want to disable it. It goes into 2wd just fine. My problem is that it doesn't always shift the tc when I need it, like if I'm going up hill in the snow it won't always shift in so I'll back off the gas then go again until it finally shift into awd. Thank you for your help :-)

I've got a 2000 Astro awd that I want to add a selector switch to, to actuate the 4 wheel drive on demand. Is this possible?

it is behind the drivers kick panel. It's a silver metal box. It's back there behind the e brake.