"John Smith" wrote in message
...
Seeking advice on following situation. I have a plastic u-tube connecting
the downspout of my kitchen sink, to the next pipe in the sequence.

I have replaced the gasket and applied TFE Paste to the male part of the
tubing that screws in to the female connector, tightened it as tight as I
dare, and yet it still leaks.

If it leaks, something is wrong. The joints don't need paste.

I had the same problem a couple years ago and just replaced everything. It
was less than $10 and doesn't leak. Unless you have absolutely nothing
better to do, that is a bargain.