Viscous Coupler Lifespan

[mikeand217]

I have a 84 G. Wagoneer with the NP229, it has 213,336 miles on it so far. I'm not sure if the t case has ever been open. But how long will a viscous coupler last if its maintained and not abused?

[mattmopar440]

Well it's only being used in 4x4 so a very long time if the fluid is kept full and clean I think mine had the original case on it with the D-shaft let go and knocked a whole in it and it have over 260K on it