A very common problem with raising and lowering the trailer, the upper piece of the telescoping vent pipe flange brakes.This flange is held in place by a set nut (like on a sink drain). The stress on the flange breaks when the plumbing pipe doesn't line up in the lowered position. Mine was broke when I bought my trailer used, the factory drilled the hole in my wardrobe countertop in the wrong location. I simply unscrewed the countertop and put it in the correct spot. I bought a new vent pipe from a dealer that had one laying around.

For anyone who has this flange break and can't get a replacement, Use (what plumbers call) a no-hub connector. A rubber sleeve with two stainless steel hose clamps. You may have to go to a plumbing supply house, because you'll want a tappering no-hub connector. One end to slip over the set nut threads and the other to slip over the 1 1/4 pipe. If the cloth cover doesn't stay up, use a zip tie to hold it.

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Les

2006 22ft towlite (replaces 97 21TL)
2006 Toyota tacoma pre-runner 4.0 L V-6 quad cab
w/ 98 chevy Powervision towing mirrors

CTWC - do you have any pics of this piece?

My plumbing vent is broken at the top, where it attaches to the roof. There looks to be about 3 screws that hold the flange to the roof - but they're all stripped from the wood, and it won't stay in place.

I could try wood glue, but that would really be a mess in the event that I needed to disassemble the unit for some reason.

I'm interested in seeing what you're suggesting. Sounds like what I'm looking for -

Seems to me that I remember someone saying that they disconnect the Vent pipe before they lower the trailer. We have never had to do this. I did use a seam ripper to take out the seam on the fabric cover that covers the bundle of wires next to the vent pipe in my classic. It needed to be washed. I then used my sewin g machine to sew velcro to make the cover go around the bundle of wires again.

Vent pipe miss alignment can be cause by broken or worn out glide blocks. This was the problem on our 95T. If the flange is broken off the ABS vent tube that goes up and down, it can be fixed by cutting a 3/16 piece of pipe off a PVC pipe that just fits over the vent pipe, then glue it on, you must use the glue that is for ABS and PVC tubing. Works great and you don't have to remove the vent from the roof.
J R Repair has new vent tubes with the flange on them, but it requires removing the roof vent to install, due to the length.