Small, yet critical, plastic window lifting part

[guyslp]

Hello All,

I've encountered my next problem, which I had solved but I knew that the solution would be temporary.

The right front passenger window recently "just dropped" into the door when it reached maximum height. I heard a loud "pop" and then the window unceremoniously dropped. I have the shop manual for the car so I took the door apart to explore what might have gone wrong.

There is a small white plastic part, oval in shape, that travels in a guide channel that's on a slightly angled tilt from the back of the door toward the front, with the front end of that channel being lower. In the center of that part is a hole where a metal knob (somewhat like a ball hitch for a trailer, but in miniature) that's attached to a plastic belt pops in. When this is all together it's what allows the window to go up or down as that belt moves. The channel in which this piece travels is thoroughly greased.

That part developed a fracture in the middle which held for a while with epoxy glue, but has given way again. I was in a real pinch when I had to resort to glue, but now want to do the repair correctly. What I'm trying to determine is what this part is actually called and if it's still available for order.

The webpage at gmpartsgiant.com for the door hardware for this year/model is here. If you click on the View Info button at the top you will get the exploded parts diagram. When looking at the shop manual and this page there is nothing that looks like this part to me, but based on the function I watched it perform I have to believe that it is a guide, but nothing really looks like that piece on the diagram. If you look at this eBay listing the thing I'm talking about is definitely the white plastic part shown in the picture.

If anyone can definitively identify the correct name for this part and/or if you know of any source for it (besides a junkyard, which I'll resort to if necessary) would you please post it here? If it's only available as part of the whole "unit" shown on eBay that would be helpful to know, too.

Thanks,

Brian

[Cadillac Jim]

The part on eBay is listed as a window regulator guide, GM part 20369895. The GMPartsGiant page shows the part as GUIDE, SLDR WDO REG-RH (PART OF 22), GM part 20369894 (the eBay part is apparently for the LH side). It looks very much like you need GM part 20369894, which is available from GMPartsGiant for $13.81 plus shipping, or from Amazon as a Dorman part for $7.50, $10 or $11.81. Although the GM lists separate part numbers for LH and RH, Dorman makes one part for either side.

I've looked at the diagram on GMPartsGiant and the tiny drawing of the part is consistent with the picture, but too small to be sure. But if the part on the eBay posting is your part, then your part is GM 20369894.

If you are not convinced, I suggest a cell phone photo of the broken part.

[guyslp]

Jim,

Thanks very much for your reply. I continued doing research and it appears that the actual part I'd like to get is part of the window regulator guide (see this one at AutoZone) and comes only as a unit. My local store is able to get this Dorman aftermarket part in overnight so I ordered one this morning. What's interesting is Dorman makes three of these: left side, right side, or "universal." I got the dedicated right side part.

I'm just hoping that this isn't an indication that I'm going to have all the others failing within the next few months. If the issue was either a "plastic pour problem" or something specific to the door in question I should be OK. If it's a characteristic of the plastic compound itself as it ages then I'm probably not. At least this sort of repair is, in the grand scheme of things, quite easy if tedious.

Brian

[KHE]

Usually when those parts start to go, it is only a matter of time before the remaining ones break. The cross section at the ball receiver area is too thin in my opinion. Heat & age cause the nylon to be brittle and they always break at the center of the interface to the ball stud. You might check with an auto glass shop to see if they carry just the nylon pieces.

[guyslp]

Usually when those parts start to go, it is only a matter of time before the remaining ones break. The cross section at the ball receiver area is too thin in my opinion. Heat & age cause the nylon to be brittle and they always break at the center of the interface to the ball stud. You might check with an auto glass shop to see if they carry just the nylon pieces.

Thanks for the input. I will check around to see if just the nylon slider is available by itself. Since the whole guide assembly was $7, and the only part that's compromised is that slider, I'd like to have additional ones around for when "the inevitable" occurs.

Brian

[guyslp]

I'm back posting about this because the problem has recurred, but part of that may be a problem of my own creation. Since I cannot embed photographs from Google Drive I will give click-through links to view them. I have four photos that show the old nylon guide as it appeared when I replaced it. The guide block moves up and down, pushing the guide to the left or right along a diagonal channel attached to the bottom of the glass, which causes the glass to move up and down.

The block with its metal ball that inserts into the socket at the nylon guide center was from the replacement part. I could not for the life of me figure out how to get the old block out, so what I did was to pop the guide off of the new block, place it into the channel, line up the existing block ball with the guide, and pop the ball into the socket. Getting them to mate was not particularly easy, so I suspect I may have started the cracking in the new guide at that point in time.

Just like the original guide, a crack developed at the 12 o'clock position on the socket which faces up when the guide is in the channel. I would think that this particular part of the guide bears the brunt of the window weight and force of gravity, along with the force of the ball pushing on the edge of the socket, when the window is being lifted.

In two pieces

Edge View - It should be noted that in service the face of the guide (light nylon part) you see would be facing out toward the door sheet metal in the channel and is positioned more closely to perpendicular to the block than parallel like it is in the photograph

Block View showing mating "teeth" to regulator tape

Block View showing outside of block

The Service Information Manual is not particularly descriptive as to how one is supposed to get the block off of the vertical aluminum channel it follows and the tape that rides within that channel. If anyone can describe, or has step-by-step instructions/pictures that deal only with getting these two pieces out of and back on to the car as a unit, I'd love to have that.

Thanks in advance for any assistance.

[guyslp]

I wanted to follow-up on this topic since I did have the driver's side now fail as well and there's some new and useful information.

First, for anyone wanting to know how to get a new regulator and guide on to the tape should definitely take a look at the thread entitled, window regulator guide replacement, on cadillacforums.com. This is the only information I've found anywhere that shows how you can do this that includes pictures. That being said, virtually everyone I know who's had failures in the regulator & guide assembly has had the nylon guide fracture where the ball stud inserts into it. It turns out there is a much easier way that will work as well or better: replacing the nylon oval guide with an alternative round guide. A gentleman at Dorman Products Technical Support suggested this, and it works.

Here are photos I took of the original passenger side guide (after gluing to restore the correct shape), the Dorman 74444 round guide, and a Dorman full replacement regulator-guide assembly:


Here's a side shot of the round guide:


And here's the round guide installed:


The only modification necessary is taking out just a bit of the nylon around where the ball stud pops in to the round guide since the GM ball stud is slightly larger than will allow you to just easily press it in. A few moments with a Dremel took just enough out to allow the ball stud to be inserted, to maintain a good, tight grip, but not crack the guide. While this may require several cycles of taking just a bit off until you reach the "pop in" point, it's much easier than trying to get a new regulator & guide on to the tape, and back into the tape and window guide channels. The round guide fits perfectly within the lift channel both vertically and in terms of thickness for easy gliding without risk of coming out of the channel. It also looks as though the design on this will be less prone to cracking.

I hope this saves a lot of people a lot of effort and frustration.

[guyslp]

There also appears to be another variant on the OEM oval clip that is available: RegulatorFix GM Window Regulator Repair Guide Clips

They're reasonably priced and eight (and counting) people have answered my question, "Will these just pop on to the OEM ball stud?," with one form or another of, "yes."

I only wish they came packaged as sets of four.