Diagnostic Aids
WARNING: This page is about a different car, the 2002 GMC Sierra and 2002 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
An intermittent hard shift may be caused by an intermittent clutch condition. With a self adjusting clutch, the clutch may be between adjustments and not give full clutch release. This might be felt by a low clutch pedal. After several applications, the clutch may adjust properly, to give the proper pedal feel.