Just replaced my Mazda 5 Speed in 88 Bronco, 215K on it, syncros were gone, talked to Trans shop guy in Phoenix (Phoenix Hard Parts, they sell on Ebay) He told me Mazda trans are good for 100 K, ZF's he doesn't recommend at all, rebuild your transfer case at the same time if you got one... Rebuilt Trans cost me $750.00, probably half of what I could have gotten it done for locally...

John