[Ski-me]

Yea, I'd be guessing the actuators are going bad. I've replaced a few up front and also the rears. I'm at 165k so if you're over 200k, they might be due. The front dash ones, I used AC Delco ones because they are harder to get to. Mainly the one in the middle, top side. I had to remove the passenger airbag to gain access to it. The second one is on the floor, between driver and passenger area. A third one is at the air inlet box.

All 3 use same one: GM 89018365 for my 04' with Auto climate control (both front locations).
A fourth one is different....I didn't touch and it's on the side of the truck.

The ones in the back, I used Dorman ones.