So according to our search, there are only a handfull of posts on creaky cranks. I'm Sure there are more. Anyway, sorry for posting about it again. I've got a creaky square taper MTB crank. I've made sure the spindle and crank were clean and hand tightened the crank with my hex wrench. Still a terrible creak. So, I'm guessing either I'm not getting it tight enough with the hex wrench or the crank has reached the end of it's days? In the experience of those who do have torque wrenches for tightening the bolts to the recommended 35lbs, would you say I'd be able to tighten my crank bolts tight enough with a hex wrench and it's just creaking anyway, or do I need to give it a bit more force and tighten it more?

Sounds like one of your cups in the frame is loose. When you pull your crank arms to check make sure you check your driveside cup first.

Spindle tapers are 1/2 degree different than the taper inside the crank arm. Well-meaning repairers often grease the spindle when installing it allowing enough mechanical advantage to stretch the crank broach to a point where no longer grips the spindle or it bottoms as you mentioned.

^ So does that mean it's probably shot and I need to get a new crank? I've never greased it, but it came from another bike and I have no idea what someone else might have done. And I've read about putting a little locktite on them, but this is a mountain bike that sees trail use and the occasional 3-4' drop, so I don't want to chance a quick fix and a crank breaking at a bad moment. If the crank is shot, is it just a matter of fitting the spindle snuggly and the locktite trick would be safe to try, or is the arm weaker and I should just turn the left crank into a bottle opener?

Mbbiker, thanks for the advice. I don't think it's the BB, though. It's a new sealed Shimano BB in a new frame installed to proper torque and it Really sounds like it's the left crank. And I've listened closely due to having read several squeak/creak threads in the past.

Might be a pedal...