Power window regulator

1989 Dodge B250

Driver’s side power window won’t go down. Last month it started misbehaving, sometimes reversing direction. Then it got increasingly balky and I had to assist the motor by pushing the window down by hand while pressing the down button. Now it won’t move at all, even with hand force plus motor. I can hear the motor turning, so I think maybe the gear is stripped.

What are my repair options? I might try to do it myself if not too difficult. New regulators are priced around $100+. Or I can get a used one online around $50. Or if it’s just a matter of replacing a stripped gear, I can get a new gear for $15.

I guess I just have to get in there and take it apart and see where the problem is. Should I give it a try, or just take it to a shop? I’ve never tried to fix a regulator, so I don’t know how much of a pain it will be.

I’ve had success with Dorman replacements. The regulator and motor combo should be about $100. I’m sure you cand do it yourself.

What’s the advantage of replacing the whole regulator and motor assembly? If the motor gear is stripped, why not just replace the gear?

It sounds like you should do this yourself. A shop is going to charge $100 or so just for the labor to open up the door and replace the needed parts. And a new regulator will be more than $100 through a shop.

You shouldn’t get a used part, you already have one and it’s inside your door. Why bother replacing one 25 year old part with another 25 year old part when a new one is available. Likewise with replacing just a gear. Buy a regulator with motor and be done with it.

You can’t get the gear. You might find a regulator or motor on line, but it is easier to replace the whole assembly.

OK, thanks guys.

The motor drive gear failure is common. You can buy a new gear for $11.


I managed to get the regulator out. Took the motor apart, and sure 'nuff, the gear was broken. Ordered a new one from Amazon (!) for $14. Should do the trick. Thanks.

but why is the gear broken ?
Kinda like a blown fuse, you don’t just blindly replace one piece of the puzzle without fixing the cause .
On a window regulator look for ease , or lack thereof, of movement and fix that too.check the slides. replace or lube as needed.
By your description ther was a large restriction in movement to start with thereby making too much work for the gear’s attempts.
Hence the biggest reason for replacing a regulator assembly.

Thanks Ken, good question. I expected to find some binding, but the window seems to move smoothly in its tracks.

There was a hefty spring preload on the regulator, and I suspect the combination of the spring preload working against a plastic gear, plus a lot of usage, plus the age of the plastic (24 yrs?) finally broke it.

But I will grease everything liberally when reassembling.

When I was at the Benz dealership, there were several models that had problems with broken plastic window motor gears

The improved and updated parts still had plastic gears, but the gear color was different, and the part number had also change

My point is this . . . perhaps the engineers simply designed a weak window motor

Make sure to take a photo of the mechanism before removing anything. Anything associated with doors and windows tends to be more complicated than it appears it will be at first glance, especially if you take things apart without taking notes or a photo, and then can’t remember how they go back together. If working on two doors/windows, finish one completely before doing anything to the second, so you can use that second one for a reference when repairing the first. Best of luck.

Thanks George, would have done so if I could, but the regulator was buried inside the door and I was flying blind when separating it from the window. Somehow I got them separated without being able to see what I was doing, by following the repair manual.

Fortunately the regulator mechanism is pretty simple and it shouldn’t be difficult to install the new gear. Getting the regulator back inside the door and reattached to the window will be the hard part. I’ll just have to use the Braille methed. :wink:

Mission accomplished, thanks to all your advice. The new gear arrived today from Amazon, and I got the whole thing repaired and back inside the door. Works fine now.

Turns out what was broken was not the plastic gear itself, but three solid nylon cylinders that lock the plastic gear to the metal regulator drive gear. Those nylon cylinders had shattered into many pieces.

The steel regulator mechanism and the drive motor are quite beefy and have plenty of life left. Of course it was the 5 cent plastic pieces that broke. Quite a pain to take out and repair, but I saved a bundle in labor costs. Glad I know how to do it now, but hope I never have to do it again!