Case 580D electric DeClutch won't release in FWD but will REV?

My 580D started today not disengaging in forward when I push the button
But will every time in reverse. Sometime it will in forward, but most times not.
This is a new one on me.
Any ideas?

Other than this the shuttle works fine Hot/Cold, been regularly serviced and never
Been apart.
Thanks,
Tom

If the electric transmission cut out works in Reverse there is no reason that it shouldn't work in Forward.
I'm thinking that it has broken the bellville washer in the forward clutch pack & it is locking forward into drive from time to time.
Is there any problem changing the 4sp between 1st & 2nd gear with the engine running?

Thanks for the reply
Interesting about the FWD clutch pack locking in?
I'm aware of the Bellville washer and what it does, but I thought when it fails the unit
Will try to move in neutral or won't move in REV.
I have none of those issues.
And yes I can change the 4 speed at idle.
It works fine other than occasionally it won't declutch in FWD. but always in REV.

It's due for a screen cleaning and oil change, so I guess when I drop the
Pan it will tell the story.

Thanks
Tom

A test light at the solenoid would say a lot

Thanks,
Yes it would, but I'm not concerned with a power issue at the solenoid.
It will always kick out every time button is pushed in REV. but not always in FWD.

I can hang a light on to see, but this is not a electrical problem , It's Hyd. or failing clutch
Pack I'm afraid.

Might as well own up to the fact that this is my personal machine which has a little over 8XXX hrs. on it
Bought new, and never been apart.
Tom

Follow Up
Changed Shuttle oil today and cleaned screen.
Both were not bad.
Screen, was clear,oil pan had a little yellow and silver flakes in it
But a lot better than what I expected.
No sludge in it at all.

Thanks for the replies,
Will keep running it until something happens
Tom