I have a 1976 Case 2670 that the hydraulic remotes have been getting slow and the last time I used it plowing the tractor nearly stalled out. I was in 2nd or 3rd powershift and stepped on the clutch pedal and now I barely have any hydraulic pressure in powershift 1 and 2 and also N. But hydraulics work perfect in 3rd and when I press the clutch pedal. Does anyone have any ideas or experience the same issue? I am thinking there is something internal in the transmission like a seal or a leaking supply line or something by passing with in. Any advise would be appreciated. Thanks.