My old tent had a zipper that sounded like a bag of chips
For years I just put up with the noise, thinking all tent doors were like that. Then I borrowed a friend's Big Agnes Copper Spur on a trip to the Red River Gorge. The zipper was quiet, like a normal jacket. I realized I'd been accepting a bad design as normal. What's a small gear flaw you put up with for way too long?
The zipper on my winter coat has been stuck for three weeks now. I tried soap and a pencil lead with no luck. You might be onto something with the lube idea.