I am having a creaking seat (post) issue. It's an aluminum post in an aluminum frame.

I'm 100% sure it's coming from the seat - does't occur when I'm standing, and I can force it by wiggling my butt on the seat when not pedaling.

I've tried cleaning, greasing, tightening all the usual spots... seat post, seat tube, qr clamp, seat rails, etc.

It's a mountain bike, and I'm trying to slowly lower my saddle to help me on descents and big drops. The creak only occurs when I lower the saddle beyond a certain point. If it's raised... no creak. The difference between the no-creak and creaking height is only ~ 1 cm.

Driving me nuts! Any help is appreciated!