170k auto box - worth rebuilding?

["Greg" <greg@xxxxxxxxxxxxxxxxxx>]

How long with the hard internals (gears etc) last on the ZF 4 speed
switchable auto box?  I have a 170k version which works okay, I fancy
rebuilding it but don't want something that's going to end up wining and
noisy.  Obviously in rebuild you don't replace the gears/bearings, just
the clutches and seals.  Anyone know if it's a good base and how long
the solenoid valves in the electronically controlled valve body last?

Greg.

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