Our patio door has been sticking since we moved in. It's getting progressively worse. We took it off and checked the rollers which were fine. The track seems to be the problem. Our 8 foot door has a long groove in which there is a long metal v-shaped track (wheels roll on this). When opening or closing the door, the track completely folds over. I looked online to get a replacement. The only thing that I see is a track cover from slide eeze (which actually looks like what we have in the groove). However, slide eeze's "track cover" appears to be something that goes over an existing track. If I replace our track with the cover only, I think that it may just fold over again. Maybe the old owners pulled out the real track and replaced it with a "track cover". I am totally confused. Any suggestions?

Mine has the identical symptoms.
Just started looking for a fix, I'll post if I get a lead on anything

My wife recalls these were Milgard windows, likely from HD. Their website was of no help.

So, I lifted the doorup and off the frame. I actually left one edge on the lip, as I only needed to get to the door off the top of the track.

The track came up easily, and it was quickly apparent the cause, or perhaps the symptom. The track should look like an "A" in cross section. Mine, in a rare fit of modesty, had its legs crossed. That's a joke son. Actually, the two legs of the "A" were pinched together.

I used a large screwdriver to pry the legs back apart, and my wife helped prep the track with a thorough cleaning. Assembly wwas a bit more difficult, as expected. The legs need to be compressed slightly, but then the track snapped back in place. I lifted the door back onto the track, all good.

Tools needed: strong back, large screwdriver, windex and a paper towell.

See below image, I will put more in an instructable.

We pulled ours out a while ago like that and did the same. But eventually, it collapsed again and again. This last time, we pulled it out and put in a small peice of rebar-like material to hold it open into it's V shape. So far, no collapse. Thanks for the help.