This is not true. Grease does not have metal in it. Some grease has molybdenum (moly) in it but it's in a far different form than the moly used in steel production. Also, a moly grease would not be a good choice for a snowmobile suspension application.these are designed to be lubed by water/snow. while i can't see grease hurting? it can on some plastic. remember most grease has metal in it.( shear strength)