Traction No power to wheels after tractor warms up???

[Peweter]

I bought a used JX95 with 400 hrs Front wheet assist , cab, loader,. At 600 hrs I am having trouble to getting power to rear wheels after the tractor warms up. It will barely untrack in Third Range 1st gear with no load! As as if the clutch is slipping but the tractor runs cool and there is no clutch burn smell. Is this a clutch adjustment easy fix or am I looking at a serious problem? Any body having similsr issues? Any advice?