You'll need a helper to replace the lift gate struts. The lift gate is heavy and you'll need both hands to remove and install the struts. The new struts are quite firm and hard to collapse by hand, so get a helper that is tall enough to hold the lift gate fully open while you install them.
Open the lift gate and have your helper hold it open. Inspect the ends of the struts to determine what type of fasteners hold them at the top and bottom. You may need a socket and ratchet, Torx or Allen drivers, a flat-tip screwdriver or a combination of these tools to remove the struts.
Remove the struts one side at a time by removing the top and bottom fasteners. If the type of fastener isn't apparent, look for a slot at the end of the strut that you can stick the tip of a screwdriver in and pry off a clip. Inspect the mounting posts. Though not normally replaced with the struts, you should inspect the mounting posts for abnormal wear and replace them as needed.
Have the helper hold the lift gate at its full-open position and align each new strut in the same orientation as the original. Use the fasteners to affix the strut to the vehicle. If the old strut had clips you had to remove to get it off, you might need to align the new strut and then give it a whack with your hand to pop it onto its mounting posts. For fasteners you had to unscrew, tighten them to the torque specification for your vehicle. Install both struts and then test the lift gate to make sure it closes and latches, and that it opens and stays up when you let go of it.
