MF 1040 4WD wont Engage

[davidshobson]

All my MF 1040 (with loader) will not go into 4WD. I bought it used a few years ago and the 4WD has always worked fine. Recently though, when trying to re-engage, the lever feels like there is no gear movement at all. Clutch engagement doesn't seem to matter. It seems like it might be a linkage issue, but the linkage goes right into the gearbox and I am hesitant to start tearing it down.

Any ideas? this tractor is great with 4WD. almost useless without it.

Thanks.