Bad idea. WD40's primary function is water displacement. It also dissolves rust, gunked up dirt and grese. Lastly, after it removes any old lubricants it encounters, it leaves a very light oil lubricant, which lasts for quite a short time. It should be used only for cleaning and of very dirty and/or stuck parts, after which a dedicated lubricant should be used. Axis recommends lithium grease for lubrication of moving parts on their pedals and I believe it would work very well on DW 9000 too.I keep a spray can of WD40 available for my pedal and I oil it before packing it up for gigs.
Go to a fabric store and buy a bottle of sewing machine oil. You can clean your squeaky parts with WD-40 but be sure to use the sewing machine oil on them afterwards. The sewing machine oil also works well on lubricating your tension rods when you change heads - just a litle bit though.I have a DW 9002 double pedal and the slave is squeaking on both sides VERY bad!!!...please tell me how to fix it....oil, graphite or what?....and let me know where to oil it on the pedal. Thanks!