I bet those bits are from the reverse brake springs springs. Good news is the reverse gear parts are right under the cover. Bad news is the trans has to come out to get at them.

At 2500 RPM my 91 350SDL is doing about 50 mph. 60 is just over that, 70 is 3,0000 and 80 is 3500.

-Jason

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.