A noisy rear hatch (squeaking or rattling) can be caused by several different things.
Over time, the hatch seals tend to dry out and shrink. As a result, the hatch does not fit as tightly and it can rattle or squeak. If so, this can often be corrected by adjusting the two posts on the rear hatch. To adjust the posts, loosen the lock nut next to the hatch. To tighten the post, turn it clockwise several turns and then tighten down the lock nut. Be careful not to tighten the post to much or the hatch will difficult to latch and unlatch.
Another possible cause is latch mechanism for the rear hatch. The latch mechanism needs to periodically lubricated. Use a good quality grease to lubricate the latch mechanisms on both sides. A combination of lubrication and adjusting the posts will often solve a squeaky hatch.
Finally, the most difficult hatch repair is caused by the rear glass separating from the hatch frame. This is caused by repeatedly slamming the rear hatch. The vibration caused by slamming the hatch closed, over time, causes the glass to separate from the frame. That's why it's important to close the hatch by lowering it down against the hatch opening gently and then pushing down on the rear of the hatch to latch it.
There are several schools of thought with regard to repairing the rear hatch. Many will tell you that the car must be taken to a professional glass service to be re-glued. While this does ensure a quality repair, it can also be very costly. There are others who have taken on this repair themselves and have successfully repaired the rear hatch. However, the hatch has to be removed from the car for repair. So, if you decide to do the repair yourself, you should have someone assist you during the removal and installation.
Repairing Separated Glass
Introduction
There are a number of different sealants/adhesives that can be used to repair the rear hatch glass. The best ones are urethane based. Probably the best overall is 3M Window Weld Urethane Auto Glass Sealant.
Procedure
Remove the rear hatch as follows:
Disconnect the rear window defroster wires (one on each side).
Disconnect the rear hatch shocks.
Lower the rear hatch but do not allow it to latch. You may place a piece of wood between the back of the hatch and the body to prevent the hatch from latching.
From inside the car, remove the bolts that hold the rear hatch hinges to the body of the car (2 hinges - 2 bolts per hinge). On early cars, there's a cover over the hinges. On later cars, the rear header panel will have to be removed.
Have someone assist you to lift the rear hatch off of the car.
Remove the trim strips from around the edge of the hatch. You'll find clips that hold the strips in place. In most cases, the clips are accessed from the underside of the hatch.
Work slowly and carefully to pry the frame off of the hatch glass. Scrapers usually work well for separating the glass from the frame.
Using an adhesive remover and scraper, remove the remains of the old sealant.
Reinstall the hatch frame onto the car with it in the closed position. Do not attach the hatch shocks yet.
Make sure the hatch frame fits properly to the hatch seals. Over time the hatch frame may have become bent and may need to be bent to get a proper seal.
Place a bead of sealant all the way around the hatch frame following the directions for the adhesive.
Place the glass on to the frame and push down around the edges to make sure the glass makes good contact with the frame. Here's a good suggestion from Vaughn Scott for installing the glass. "With the glass upside down, maneuver it so that it's behind the car with the rear edge facing forward. Place the rear edge of the glass in the rear of the frame and rotate it forward until the front of the glass is about a foot from being in place. Have one person hold it in place while the other person goes inside the car and takes the weight of the glass. Then the person outside of the car pulls their hands out of the way and the glass is lowered into place."
Using the adhesive, fill in any gaps between the glass and the frame.
Allow the adhesive to cure for at least 24 hours.
Reinstall the trim strips and clips. This may require unbolting the hatch hinges.
