[eschaider]

I think common sense plays a significant role here.

If threads are 2, 3, 4, 5, or more years old, the original thread participants have long since moved on. Some original participants may no longer be active, some may have sold their rides (in the 5+ year window), and others may have even passed away!

For all intents and purposes, as of that last posting, the thread subject has been resolved to everyone's satisfaction or capability.

If you have what you believe to be significant new information on the subject matter, starting a new thread would be the right approach. If you have questions on the subject matter, start a new thread with your question. Resurrecting the old thread is probably not as good an idea.