[arcticdude]

Are you using a wet spline pto or a greased spline?

The greased spline on some Birds has a “fretting” issue that damages the splines. Supposedly a wet spline system doesn’t experience fretting issues. I don’t know if any owners have had a wet system long enough to actually test that theory of wet splines being better.

Frequent greasing can also reduce the damage, though the interval bantered about is 3500 miles for routine greasing.


I must add the units affected so far are all Series 60/Allison combos, while none of the C-13/Allison units have yet to show any fretting occurring.