It is the actuator, look this up on Blazer forum, someone will tell you step by step how to fix it!! You will have to loosen the inner panel and get your hand in there and find the proper linkage to pull on.
Yes it is.
no, they are totally different sizes and profiles
big hammer
To remove the tailgate lock on a 1989 S-10 Blazer, first remove the cover over the inside of the tailgate by removing the bolts on the side and on the handle. Pop the vinyl away from the tailgate. Then remove the bolts holding the lock on and remove the lock.
take it to a transmission shop
Remove the dash assembly to gain access to the blend door actuator.
Open the tailgate. Notice the two small Phillip head screws along side the taillight assembly area. Remove the two screws and you can wiggle the taillight assembly out so you can change the bulbs.
its locked while window is down.
Open up the tailgate/hatch. Look at the inboard sides of the taillightsThere are two black Phillips-head screws along the body seam, holding the assembly in. Simply remove those screws and pull the assembly straight out. If there are tailgate struts blocking the screws, you'll need to move them aside.
Had this happen on my Blazer the hose came disconnected in the tailgate and the washer fluid was emptying into the tailgate. You need to take the inside panel off to get at the hose to reconnect. Also dry your tailgate out. Needless to say I no longer use this option.
These models came stock with a release button below the cigarette lighter. If you look directly to the right of the radio there should be a button to push that will release the glass and then once its open, your tailgate should open once you do it manually. Hope this helps you
from the tailgate?or from the glass upper?need more info