A great many of them weren't dipped in anything. I was a dealership mechanic from 1970-1978 and saw thousands of new cars in that time. Most control arms, upper and lower, and rear leaf spring plates were installed 'as stamped' with nothing more than the residual oils used in stamping on them. Strut rods weren't coated either in most cases. Winter delivered new cars often showed rust already growing on those parts when they came off the truck. The factory didn't care what the underside of the car looked like after a month of driving. New replacement parts were always coated much like abodyjoe is showing to prevent rusting in long term storage, as were replacement brake drums and rotors, and sometimes, but not always, cylinder heads and other iron forgings & casings. A replacement power steering pump might be dipped in cosmo, plastic bagged and boxed. Or it might be left raw and wrapped in vapor paper then boxed. Seemed to be no set rules, but left to the discretion of the vendors.
. I like how the Gold tone came out on mine.
