Weatherstripping Replacement - Silence Is Golden

Once we freed the outer belt weatherstrip from the door, a few minutes with some cleaning agents and a shop towel got our door shell ready for the new parts. Wow, that's what shiny paint looks like, huh?

In this comparison photo you can see the back side of the outer belt weatherstrip and how much more "fuzz" is on the new piece compared to the 19-year-old part we removed. It's also very flexible, while the original feels like a hard plastic part after all those years in the sun.

Carefully place the new outer belt weatherstrip (PN 814523A, $49.95 pr) on the door shell lip, ensuring it's properly seated within the window channel weatherstrip and secure with three aluminum or stainless steel 1/8-inch short rivets. Our window channel weatherstrip was replaced about five years ago and was in excellent shape, but if yours is dried and cracked Mustangs Unlimited carries these as well, and now is the perfect time to install them with the door panel removed. You can reattach the side view mirror now too.

Our new outer belt moldings came as a set with new clips under PN BM87 at $72.95 for the pair. We reused most of our clips, but replaced any missing or damaged ones with the clips in the molding kit. Use the longer 1/8-inch rivets to secure these. Line up the notches in the molding with the clips and press down while sliding the molding forward onto the locating tab on the mirror body. Secure with the new screw from the molding kit.

The outer belt weatherstrip and belt molding replacement is complete and makes the car look so much better already. All that's left is to replace the inner belt weatherstrip on the door panel and reinstall the door panel.

The inner belt weatherstrip is secured to the door panel with staples. The best way we found to remove the weatherstrip was to wedge a screwdriver between the panel and the weatherstrip under each staple and twist the screwdriver to pry the staple out. Repeat until all staples are free and then remove the weatherstrip from the door panel.

Once removed, we once again compared the new and old belt weatherstrips together. The old weatherstrip had worn down to bare rubber, and was rock hard, most likely the main cause of our window squealing. The new inner belt weatherstrip is PN BM11 for '81-'93 Fox Mustang and are $54.95 for the pair.

Carefully place the inner belt weatherstrip onto the top of the door panel and ensure it's located properly using the old weatherstrip's stainless trim witness marks as a guide. Drill 7/64-inch screw holes and secure with Mustangs Unlimited's inner belt weatherstrip screw kit (PN PE881, $3.95). Alternatively you can have a trim shop staple them on like OE, or you can use rivets. A dab of black paint will hide the shiny screws if it is a concern.

Evenly spaced, the retaining screws from Mustangs Unlimited do a fine job of securing the inner belt weatherstrip to our door panels. With the inner belt weatherstrip secured you can reinstall the door panel using the reverse of the removal procedure previously outlined and move on to tackling the other door.

One last before and after shot will no doubt convince you that this is a worthwhile repair for the aging Fox Mustangs out there. Above is our driver door with new inner and outer belt weatherstripping and new belt molding. Note how the two belt weatherstrips touch, with the inner overlapping the outer. Now take a look at the yet to be repaired passenger side with ruined belt molding and belt weatherstripping so hard that when the glass is lowered a gap between them remains. For about $185 in parts we had our Mustang looking and functioning better. Of course it might cost a bit more if you need other door parts (panel clips, arm rest pad, and more).