Our 84 Firebird has over 200k mi with plenty of normal duty cycles on the lights. Since purchased new it is still working just fine (knock on wood) for the last 25 years. I thought maybe it had a simpler or more durable design than the Corvette C4. But it seems to have the same basic gear design of other cars such as the C4 Corvette which have proven to not always be durable. There are some threads here on same/similar problems to the C4 - the nylon pins shearing/disintegrating inside the housing... but not as many threads as I would have expected.

So I'm curious - is it common to have such longevity (20-25 years; 100-200k mi) out of the Firebird's original headlight motor gear assembly? Or is it an anomaly?

 

hit or miss

 

maybe you just got lucky

 

I wouldn't be surprised if the early units were built better & with stronger parts, than later model ones. Companies commonly lower their standards on the parts, to cut costs. Cut a couple of cents per unit...Multiply that by 100,000 cars & suddenly 2 cents is a big savings.