While in park and neutral, the vehicle has a rev limiter of about 4k RPM so you dont blow your engine.
While at a run, I would say it might be time to change your tranny filter. That is almost like the valve bodies are sticking. I would wait until someone else has a chance to give their opinion on your shifting issue.
_________________________
WizAire CAI w/9" K&N & HV3, 2.5" d/p w/h/f cat, Cobra CB, PowerSlot slots w/Hawk HPS, GR-2s, GMPP handling kit, NextLevel STBs, Pilot Sport A/S Plus tires.
98 L36/MM5
RaC