My 87 GN always had an annoying problem with the power window.
It would go up nice an easy but going down it was jumpy, and made a horrible vibrating noise.
It also had the annoying problem of pulling out at speeds over 80 MPH.
A couple of days ago, I got inspired to attack the problem since my power lock quit.
I took the door apart to try and figure out what was going on.
Now when I say I took the door apart-- I took it ALL apart.
The previous owner must have been in there, and he was a hack.
There was no vapor barrier and the sound deadener was a shredded mess.The power window switch was a big blob of hardened glue and JB Weld with wires sticking out of it. There was no connector.
I had to cut the wires to free the panel.
The next day I had to go to the junk yard and get the connector endoff the 85 Monte I saw in there not too long ago. (Hoping all along they didn't crush the car already.)
Back home, the entire regulator assembly was removed and the grease that was used had gotten very thick and dirty it was so tacky it was like tar.
The window felts, stops and pins all came out and the glass itself was next.
I cleaned all the regulator tracks it took 2 1/2 cans of brake clean and a cup or two of gasoline to disolve that tarry messy lube.
Then I saw the culprit; one of the regulator rollers had a flat side and wasn't round anymore, I deduced that this was causing that vibrating effect on the way down.
So I went to my neighborhood parts store and ordered some regulator rollers, a power window motor, I bought a power lock actuator from Rock Auto and a window sweep weather strip form 1Aauto.
The regulator rollers came in they were a Dorman/Help! item and they didnt look the same, turns out they were for manual windows but I took them anyways. The Power lock actuator was here too.
I compared the rollers and they were the same size it is just the stantion they are mounted on they were able to be pryed off and installed on the existing power window regulator stantions.
So the regs are all clean. New rollers on.
I re-install the assembly, and before I hook up the power winow motor I compare the speed of the new unit to the old one.
I do this by running them outside with the harness connected.
THEY ARE THE SAME SPEED!
So I figure I'll just keep the good ole AC Delco one (its an replacement motor not the original) and either return the parts store one and get my $45 back or just keep it on hand for future generations when these parts are no more
I lube up the regulator channels with this really neat lube i got from Radio Shack a few years ago, its a Lube Gel and its not supposed to break down, attract dust, be affected my water or moisture and keeps its lubricity in extreme temps.
So I go ahead and install the assembly --that is far easier to type that than it is to do.
I dont have a heavy duty rivet gun so I was stuck with using short pan head screws and nylock nuts (which is really a good alternative) but makes for a PIA job.
I hook up the battery and the do a test run without the glass installed the regultor assembly goes up and down as designed. Next, I install the glass.
Once again easy to write it. It takes some finesse and a second pair of hands (which I dont have) would help here.
Another test the window goes up smooth and quick,
(must be that Lube Gel) and nice and noisy on the way down! It sounds like a ship's horn in the distance!
Damnations!
I added more lube here and there and still no change.
It was worse than before
Time to quit and go to bed.
I get back to my project and I was thinking of different things to try it wasnt until I held/pulled the glass upward as the window went down when I made progress.
The noise and vibration stopped when I took the weight off the motor when the glass went down.
So it must be the motor, OK partially disassmeble the regulator undo the motor and intsall my spare (happy with myself for not rturning it.)
Like I said before it's easy to type "install and remove" but doing it takes time but its even harder with the weight of the glass
Well the moment of truth: test up- smooth and really fast! and down- smooth, fast and quiet! Yay!
I now deduced that the tarry lube was actually making it easy on the old worn motor since it was slowing its down ward travel, when I cleaned it all up and it was free traveling thats where it made the vibrating worse.
Oh yeah the power lock actuator was straight forward repair very easy to access and install.
parts:
Dorman:
Power window motor-WL4200 or 742-150 or 742-100
Help! Regulator rollers- 74444 (small for slide hiegt adjuster)
74407 (larger swivel type for regulator track need to be pulled off manual window stantions)
Radio Shack Lube Gel: discontinued but I understand it is available at hardware stores as "Super Lube"
Well stay tuned I have some pics and my home made vapor barrier and sound deadener to install.
It would go up nice an easy but going down it was jumpy, and made a horrible vibrating noise.
It also had the annoying problem of pulling out at speeds over 80 MPH.
A couple of days ago, I got inspired to attack the problem since my power lock quit.
I took the door apart to try and figure out what was going on.
Now when I say I took the door apart-- I took it ALL apart.
The previous owner must have been in there, and he was a hack.
There was no vapor barrier and the sound deadener was a shredded mess.The power window switch was a big blob of hardened glue and JB Weld with wires sticking out of it. There was no connector.
I had to cut the wires to free the panel.
The next day I had to go to the junk yard and get the connector endoff the 85 Monte I saw in there not too long ago. (Hoping all along they didn't crush the car already.)
Back home, the entire regulator assembly was removed and the grease that was used had gotten very thick and dirty it was so tacky it was like tar.
The window felts, stops and pins all came out and the glass itself was next.
I cleaned all the regulator tracks it took 2 1/2 cans of brake clean and a cup or two of gasoline to disolve that tarry messy lube.
Then I saw the culprit; one of the regulator rollers had a flat side and wasn't round anymore, I deduced that this was causing that vibrating effect on the way down.
So I went to my neighborhood parts store and ordered some regulator rollers, a power window motor, I bought a power lock actuator from Rock Auto and a window sweep weather strip form 1Aauto.
The regulator rollers came in they were a Dorman/Help! item and they didnt look the same, turns out they were for manual windows but I took them anyways. The Power lock actuator was here too.
I compared the rollers and they were the same size it is just the stantion they are mounted on they were able to be pryed off and installed on the existing power window regulator stantions.
So the regs are all clean. New rollers on.
I re-install the assembly, and before I hook up the power winow motor I compare the speed of the new unit to the old one.
I do this by running them outside with the harness connected.
THEY ARE THE SAME SPEED!
So I figure I'll just keep the good ole AC Delco one (its an replacement motor not the original) and either return the parts store one and get my $45 back or just keep it on hand for future generations when these parts are no more

I lube up the regulator channels with this really neat lube i got from Radio Shack a few years ago, its a Lube Gel and its not supposed to break down, attract dust, be affected my water or moisture and keeps its lubricity in extreme temps.
So I go ahead and install the assembly --that is far easier to type that than it is to do.
I dont have a heavy duty rivet gun so I was stuck with using short pan head screws and nylock nuts (which is really a good alternative) but makes for a PIA job.
I hook up the battery and the do a test run without the glass installed the regultor assembly goes up and down as designed. Next, I install the glass.
Once again easy to write it. It takes some finesse and a second pair of hands (which I dont have) would help here.
Another test the window goes up smooth and quick,

Damnations!
I added more lube here and there and still no change.
It was worse than before

Time to quit and go to bed.
I get back to my project and I was thinking of different things to try it wasnt until I held/pulled the glass upward as the window went down when I made progress.
The noise and vibration stopped when I took the weight off the motor when the glass went down.
So it must be the motor, OK partially disassmeble the regulator undo the motor and intsall my spare (happy with myself for not rturning it.)
Like I said before it's easy to type "install and remove" but doing it takes time but its even harder with the weight of the glass

Well the moment of truth: test up- smooth and really fast! and down- smooth, fast and quiet! Yay!
I now deduced that the tarry lube was actually making it easy on the old worn motor since it was slowing its down ward travel, when I cleaned it all up and it was free traveling thats where it made the vibrating worse.
Oh yeah the power lock actuator was straight forward repair very easy to access and install.
parts:
Dorman:
Power window motor-WL4200 or 742-150 or 742-100
Help! Regulator rollers- 74444 (small for slide hiegt adjuster)
74407 (larger swivel type for regulator track need to be pulled off manual window stantions)
Radio Shack Lube Gel: discontinued but I understand it is available at hardware stores as "Super Lube"
Well stay tuned I have some pics and my home made vapor barrier and sound deadener to install.