05 Tahoe Transfer Case Problem
 

While driving on the interstate it went into "neutral" and coasted to a stop. Made a whirring noise when attempting to move fwd and rev. Put it in 4AUTO and drove it away just fine. Then 2HI worked again. When I got home I shifted from 2HI to 4AUTO, no problem, back to 2HI and nothing. 4AUTO again worked fine, but there was a slamming noise when it engaged, sitting still, trans in "N".
I am thinking actuator motor or connection. Thoughts?

Does decoder sensor ring a bell with anyone?

I just had similar problems with my 04 Hoe. It would start up in a random mode each time. Most of the time Auto 4wd, but sometimes 4 Hi or even neutral.

Dealer ended up replacing the transfer case control module; didn't fix it. Then the dealer replaced the transfer case encoder motor and the 4x4 selector switch and that cured the problem.

It was probably just the switch. I told the dealer I thought it was, based on everything I'd read on the Internet, but all they care about is what codes the truck's computer says, then they replace those parts. I'm just glad I didn't pay for it (CarMax warranty).

Good luck. The selector switch is only about $50 from Rock Auto.

It was the encoder motor.