Power windows... #$%%@

[Ogre]

So I decide Saturday morning it would be a good time to start in on the power windows....

Driver's window... OK.. takes about 1/2 hour, but I get it all dismantled, what i could reach I cleaned out, and a nice fresh coat of white lithium grease...

Ahhh.. much better... wait.. why'd you stop... what?!?!? OK so the switch isn't very good... so now it's hanging out the side waiting for me to go get a replacement...

Alright... let's try the driver's side rear window... It will roll down about 1/2 way and make a horrendous grinding sound... it won't go any further even whan "manually assisted".

It goes back up just fine, and then makes the same grinding sound when hitting the top.

Because the window won't go all the way down I had a heck of a time getting that door panel off...

How do I get in there? It's an 86 GMC Sierra Classic Burban -- I.E. one piece door frames with the power stuff bolted inside...

I think it needs the new regulator track, but I can't even figure at this point how to get to the old one to look...

[BigRed]

Mine has the exact same problem as that and it's the driver's side rear window also. Same grinding noises and everything. I know I need to fix it, but that's low on the priority list. I think it's a worn motor, but maybe you're right about the track. If you figure it out, please let me know.

[Ogre]

Low priority but also (hopefully) very low cost

Front window was (virtually) free to fix up

[MattA]

I have a little experience with window motors and can just about guarantee that it is the motor. They have a gear inside the motor that strips out over time. You can usually hit the glass when it hangs on the way down and it will catch a good gear and continue.

They will either strip internally, or stop working when the motor heats up and trips the internal circuit breaker.

Usually not a huge deal to replace, but be careful with the spring loaded regulators out of the door when you take a motor off they can bite.

matt

[Eyegore]

I agree with Matt, I just had the same problem, the grinding is the motor. I had a shop replace the motor I pulled out from the wrecking yard, $32 for the motor, $30 to install. If your mechanically inclined you could do it yourself, remove the window glass, vent window assembly then the whole regulator with the motor attached.
When the assembly was out we bench tested the motor to make sure that was the culprit, it was. Reinstalling everything was more difficult, getting the glass back on the regulator track was the toughest part as I watched on. But after watching I believe I could tackle this on my own. If you do try t do it yourself just remember to remove all brackets, espically in the opening behind the door latching mechanism, that opening is where the regulator with and motor will come out. Or you could just check with a glass shop or wrecking yard that replaces glass, they'll probably do everything for $120, that the other quote I got for fixing it.

[Ogre]

What about the grinding when I roll it back up though? It's got the same sound when it hits the top as when it stops 1/2 way down... strong and smooth up to that point and down from the top to the dead stop...

Anyone have a good motor hanging around ???

[Eyegore]

Your desribing exactly what happend to my 82. 1/2 way down; grind, roll up; grind. The first time I encountered this was on my 86 burb, just like BigRed's, rear drivers side door. Went to a wrecking yard that replaces glass, he said it's common for the motor to go out with the symptoms described, rarely he said does the regulator go out.
Do a test, you'll have to pull it apart anyway even if its the regulator. Pull the motor off and bench test it using alligator clamps to the battery. Let it run up, you'll here a grind, then reverse the clamps to roll down, grind. Then replace the motor.
I know its common to expect the worse, but you can pick them up at a wrecking yard, motor & regulator.