First time here. Not sure if I'm in the right spot.
I've got an issue with my tailgate regulator. The rear window goes up about 3/4 and then the roller rivet pops out causing the glass to dislodge and slope sideways. What to do?

 

You are in the right place. Sadly I'm not the one to help you. But I'm sure there is someone who can.

 

Thanks Christine, good to know. Best!

 

I have a power window regulator for my K5 in a box in the attic above my garage somewhere, but rather than finding it and pulling it out I just looked up some pictures for one that is for sale on eBay to familiarize myself with it again. So you are talking about the rollers that are on the regulator that run in the tracks on the bottom of the glass itself. They are jumping out of the tracks at a certain point of motion. Is there any damage to those tracks on the bottom of the window that would allow the rollers to jump out? Any damage to the rollers themselves? From what I can remember when I swapped out the manual regulator in my '74, it was a bear to get the tracks on and off the regulator; at least on mine things were a very tight fit. Once they were in there, it should be fairly difficult for them to get back out.

If the tracks show damage, they can be replaced as they just bolt on. The rollers are a bit trickier. I believe they were an injection molded nylon part and I do not know of an aftermarket alternative.

When the window is going up, does it stay in the weather stripping channel relatively well? Does it go up evenly?

A lot can go wrong with these regulators and the window tracks, weather stripping, etc. as things age and shift around.

*EDIT* -- Here are a few options that I could find for replacement rollers--

1. AMD has a replacement roller, but I do believe that the application is for a side door regulator. I'm not sure if it is the same as the rear window regulator. Might be worth a purchase to see as it is considerably cheaper than the next option --> https://www.autometaldirect.com/wind...hevy-gmc-truck
2. eBay - qty 2 replacement rivet rollers that say they are for the 73-91 manual or power rear window regulators --> https://www.ebay.com/itm/171998757178
3. AMD part that looks like the eBay part in #2 --> https://www.autometaldirect.com/wind...y-gmc-ck-truck44

**EDIT 2**
LMC Truck has everything for cheaper --> https://www.lmctruck.com/body-components/bed-tailgate/csb-1973-91-tailgate-and-components_with-removable-hardtop
Item #4 for the track and item #17 for the replacement roller.

 

Thanks for your reply.
I replaced the glass channels thinking that was the problem ($225). Then I thought it might be the cam channels (I think that's what they are called?) where the roller/rivet sits, so I switched them but still had the window dislodge and slope to the left anyways. So the only thing I can think is the regulator is the issue. Does it need to be replaced or can it be adjusted so it doesn't pop out from the roller is what I need to know. I'm hoping its a simple fix otherwise with the exchange rate I'm into a another $300 bill to fix this problem for my old truck that I love dearly. Bought it brand new off the lot in 1990. Its a rust bucket now but it still gets the job done when I need it to.

 

The rollers aren't that expensive if they are shot and no longer are round and/or a tight fit into the channels they ride in on the window sash. I linked to them in my edits above. I'm betting that the one that keeps on popping out is worn down further than tolerable and is why it is popping out. .

 

No, the rollers are new but the cam channels they sit in are not... actually worn down quite a bit. Maybe that's the culprit? But maybe not since I switched them and still got the same problem on the left side again. The only other thing I can think of is the regulator arm or more likely the gear are worn or broken. Will have to check once the rain stops, if it ever will. Thanks anyways. Best!