Re: Squeaky double bass drum pedal
+1 on the DO NOT use WD40 part. At the very least, WD40 in this situation will attract more dirt than you need and makes things even worse over time. Plus it's messy if you're set-up on somebody's nice carpet too.
I also recommend taking that thing apart and cleaning it and lubing it back up with the proper grease. If you have to replace a part, then that's what you have to do. Double pedal linkage parts are put under a lot of stress, which is why they're designed quite a bit more robustly today than they were back in the early 80s.