Bobcat T595 lift cylinder drift

I have a Bobcat T595 - if lifting arms and closing grapple at same time with load in grapple, lift arms drift down. If load is heavy enough, arms drop to the ground pretty quick. Both work fine if used independently, issue only occurs when lifting and closing grapple at same time. Checked system pressure at quick couplers, have 3500psi. Removed load check valve for the lift cylinders, no issues. Checked main pressure relief valve, no issues. Any ideas? Thanks