I have a Ford 9" 3.75 with an Auburn cone type LSD I have read on various sites, as they wear, they introduce fine metal dust into the 3rd member Any have experience or knowledge of the above ?? Ricky.
Yes it will. Here's an article with a lot of good photos and info on how to rebuild one, but as you can see the cone clutches are metal on metal, and any time the clutches engage there will be microscopic metal coming off of them. https://www.forabodiesonly.com/mopar/ams/how-to-recondition-a-sure-grip-cone.28/
I've had a bit of experience with them in Aussie 9-Bolt Borg Warner rear ends. Yes they do add a fine metal dust into the oil. But it is no worse than clutch fibre dust. I've pulled them down at over 100k and they were fine. The only issues I've had was stripping the splines in the cones [caused by burnouts with worn clutches] They are real easy to pack shim washers between the gears and cones to tighten them up. I've had the bolts that hold the 2 piece casing come undone [a BW problem] but drilling the bolts and safety wiring them fixed that. If you're really worried simply change the oil on more frequent intervals [than 100k]