They look like have some form of bronze plating to me.Never had one apart but here is a couple of pics of a transmission. Doesn't look like it.
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Thank you for confirming that and my suspicions . The pics show it and good engineering practice would dictate that would be the best approach. It also explains the odd mini trace of bronze dust in the oil, more so then say the pump shaft bushings would normally produce if one goes looking for it. Most never notice.According to the "Porsche Engineering Magazine", 2003:
"The 4th/5th-gear selector fork is an aluminum diecasting; the forks for 1st/3rd gear and 2nd gear are steel forgings with a brass antifriction layer on the contact surfaces."