We haven't had any problems with the Diff Lock, but have had some problems with the Collar Shifts (it was discontiued a few years ago)-is the linkage hooked up? Has the "feel" of the pedal changed? Did it work properly before? When are you engaging it? Do the Brakes and other Controls work properly?
I have had no issues with the collar shift when following the manual when shifting (waiting the five seconds between shifts). The tractor is a one owner and has less then 200 hours on it.
The feel of the differential lock pedal is different. I was using it two weeks ago plowing snow and noticed that when I finished the driveway that it was no longer working. All other things are working proper. There is no linkage just the pedal that attaches directly to the transmission case.
I am hoping for something like a shear pin or something easy.
I'd make that call sooner rather than later because if something inside the cases has come loose or broken, you don't want it getting caught up in the other gears and causing one very expensive repair job!