It's the little things that can make a car enjoyable-or unpleasant. Sagging door hinges, loose sun visors, heater controls that don't work or have knobs missing-they aren't enough to turn you off of a car outright, but each time you drive the car and come in contact with these worn pieces, they detract from the enjoyment.
A common problem on older Fox-body Mustangs is the window-lift mechanism, which tends to wear out, causing the windows to not line up properly every time you roll them up. Eventually, putting the windows up is a two-handed operation-one on the crank or power switch, one on the top of the glass to guide it and keep it straight. As if that's not annoying enough, about half the time the window doesn't seat fully at one of the top corners, and you don't realize it until rain or a nice stream of soapy car-wash water comes flowing in.
Begin by removing the door...
Begin by removing the door panel-there's a combination of screws and friction tree clips, as well as the wire harness for power windows, locks, or mirrors, if your car has them. This car has power locks with manual roll-up windows.
The problem is commonly attributed to a pair of nylon bushings that ride on a vertical tube inside the door. There's no doubt these wear out, but as we found out, they aren't the only reasons for the window misalignment. The glass is attached to the window-lift mechanism by way of two disc/washer assemblies (that mechanism itself rides on a vertical tube). These plastic washers are halved down the center and installed with one half on each side of the glass, secured with a rivet running through the first, through a hole in the glass, and into the second half of the roller.
Over the years, these plastic wheels wear, as does the rivet. After we got ours out, we slapped the dial caliper to them and found 1/16-inch of play versus a new assembly. That doesn't sound like a lot, but the two of them had 1/8-inch of slop combined, in opposite directions, and that compounded all the other slop in the window-lift mechanism. The further the window lift traveled, the worse the misalignment got. It also perfectly exemplifies how just 1/8-inch of play at a pivot point will translate to much more misalignment the farther away you get from that pivot. By the time you get to the top edge of the window, you can be out by over an inch or more.
You can remove the door panel...
You can remove the door panel without this interior trim tool, but you're very likely to pull the friction clips through the door panel without it. Having one in your toolbox will make future interior projects much better.
Replacing just these retainers offers at least one big advantage over replacing other parts-the window-lift mechanism doesn't have to come out of the door, so you don't need to completely readjust the window lifts (there are few jobs we dislike more). Because the lift mechanism stays in the car, fixing this problem doesn't actually take that long.
We bought a Door Glass Mounting and Retaining Kit from Fox Mustang Restoration for $10 and went to work. From start to finish, the first door took us about half an hour, with photography. The passenger side was fine, but if we needed to replace it, it'd be about 15-20 minutes now that we know what we're doing.
When it was done, there was still a little diagonal tipping back and forth as the window went through its range of travel, which we've traced to those bushings on the vertical track being worn, but it's slight compared to what it was before, and the window straightens itself out when it gets to the top of the window frame. The window not only doesn't get cocked sideways in the frame anymore, but it fully seals at the corners now, too. The $10 and 30 minutes we spent doing this little project was a great investment toward the overall enjoyment of our car.