automatic transmission probelm.. =(

The gears shift nicely when not warmed up. The car will go 1 -- 2 and get stuck on 2 once the car is warmed up. Sometimes if i shut off the car and turn it back on it works again (shifts normal). Also sometimes if I keep it under 2k rpm while it shifts, it works... would switching to Pennzoil Synchromesh or BG Synchroshift help at all???

would switching to Pennzoil Synchromesh or BG Synchroshift help at all???

No, those are gear oils that are used in manual transmissions. You should use the right ATF that is specified for the car. Try checking your fluid. (Remember in park, vehicle running at operating temperature) Smell it and see if it seems burnt, if it is it should be something other than red. If thats the case, it might be time for a new filter and transmission flush.