My boss had a '97 with a 5 spd, at around 200,000 it lost 5th. I pulled the tailshaft housing pulled the old nut and washer out and told him to go down to the dealer to get new ones.
He took the gear with him and they sold him the gear, washer and nut. I made him take the gear back as there was just normal wear on his old one. I reinstalled gear, locktited,torqued, and staked the nut. Filled the case with Mobil one gear lube. When he traded it off it was still going strong. Dave