If your factory moonroof (the large glass kind with the hand crank) generates wind noise at highway speeds, here's how you can fix it.

1. First make sure it is properly seated. Take off the roof, and reinstall it, dropping the rear from at least 20 cm (8 inches). If you drop it from less than this height, it may not seat properly.

2. Test for any play in the front hinges. First push down on the front edge of the moonroof. Stand outside the car and push up hard on the moonroof anywhere near its front hinges using your fingers (one side of the car at a time). If you see the front of the moonroof move up at all, you have play.

3. Take off the 2 screws at the bottom of each hinge (the hinges are the metal tongues attached to the glass). This will uncover a third screw in the center. Inspect the seals around the holes in the glass.

If they are damaged, or if anything seems worn, spongy or bent (this can happen with repeated removal and installation), replace the hinges as explained in step 4. If everything appears solid, then tighten all 3 screws on each hinge as tight as you can.

4. If replacing the hinges, buy two new hinges (part numbers MB641203 and MB641204; I paid only $17.11 each at Rockland Mitsubishi). Look carefully at the parts before installing them - some parts are tapered and must be installed with the thick end toward the car's centerline.

Also, don't expose the adhesive until you've temporarily assembled the parts and checked the roof's fit. Then peel off the backing and reinstall, tightening everything.

5. If you still have wind noise from the front of the roof, you will need to adjust the fore-aft position of the roof. Pull down the rear of the plastic cover behind the crank, and you will see that the crank assembly is attached with 3 bolts. With the roof off, loosen these bolts and slide the crank assembly about 2 mm toward the front of the car, then tighten the bolts. Use a screwdriver, not a wrench, as these bolts can break if too much torque is applied. You may need to experiment a few times to get the exact position that stops the wind noise.

6. If the rear of the roof creeps up while driving due to aerodynamic lift, try closing the crank all the way, and then backing it off a portion of a turn until it reaches the spot where the handle fits into a dimple. From there, the crank will not turn, so the roof will not lift, and if you are lucky, you will not have wind noise. If you still do, you must reach back and close the crank fully from time to time.

If you don't mind messing up your interior very slightly, you could drill a new dimple in the correct (fully closed) position. I chose to do something better: I replaced the crank with a motor! (see number 7)

7. Replacing the crank with a motor and gearbox is a great solution that completely prevents the rear of the roof from lifting up by itself. Plus, it brings the sunroof mechanism more in line with the rest of the car (I always found the manual crank awkward, and cheap compared to the engineering of the rest of the car). I used a power window motor, which has the gearbox built in. You will need to build a bracket to mount the motor, and a coupling between its output shaft and the disk that the crank mounts on. I installed an orange-illuminated switch marked ROOF in the console that matches the other switches quite well. Now, opening and closing the roof is a pleasure, with the gentle touch of a button.

8. If nothing above cures your wind noise problem, then the weather-stripping is probably excessively worn or damaged. Before replacing it, buy a roll of thin foam rubber weather-stripping for houses, with the adhesive backing. It is available in a very dark gray, which makes it hard to notice.

Try attaching it to the car's roof along the perimeter of where the sunroof fits. It should get rid of any remaining air leaks. An alternative, less noticeable, place to install it is on the bottom of the glass, exactly above the innermost factory rubber weather-stripping.

Provided by:

Lloyd Wihl

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