The pwr antenna had stopped working about a year ago but the radio still works fine.
When power is turned on you can hear the mechanism cycle up and when power is turned off you can hear it cycle again, but in both instances the antenna stays fixed in the extended position.
Could something come loose and seperate or is getting a new antenna from a wrecking yard my next task?
What should I expect to pay for one?

the gearing inside probably stripped.

Or the cable broke. Take the unit out and inspect. It probably can't be repaired.

I'm thinking $15-30 from a junkyard but a power antenna isn't something you want to get from a junkyard.

You can buy new ones (the whole unit) on e-bay.

fuhgeddabout it. After going through 2, I just bought the factory non-power unit. Cost about $28 and the radio reception is much better.

good point, but there is a certain coolness factor about an antenna that shoots up and down.

Do the smart thing. Replace it with a power antenna from a 99. That'* the newest I could get. Both work flawlessly, and should give me many years of service.

Did you buy new or used and what did you pay?

A complete new unit is about $75 from gmpartsdirect. Plus shipping.

Swapping it out takes 20 minutes.

Order two. it saves freight, and you'll need it.

Please explain why I need to order 2 of them???

"Please explain why I need to order 2 of them???"

Because you'll be doing the swap again someday soon.

They tend to break a lot.