GMC 2008 Envoy - Manual (Page 350)

Backglass Wiper Blade Replacement
1. Lift the wiper blade assembly up and out of the
park rest position.
2. Pull the wiper blade assembly away from the
backglass. The backglass wiper blade will not
lock in a vertical position, so care should be used
when pulling it away from the vehicle.
3. Rotate the wiper blade assembly, and pull it off of
the wiper arm. Hold the wiper arm in position and
push the blade away from the wiper arm.
4. Replace the wiper blade.
5. Return the wiper blade assembly to the park rest
position.
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