05 226SAN TE,V Drive Oil Pressure Warning Light

All-
The "do not operate over 1200rpm if light stays on" warning light functions normal for the first hour of the day (goes off immediately when given throttle, even below 1200rpms). Eventually, however, the light will start staying on.
After floating for a few hours, however, the light will operate properly again and go off once above 1200rpms. I dropped the oil pan off of the bottom and it was clean...no metal shavings or foreign material. I also replaced the small oil pressure sensor thinking it may be fouled. Any thoughts? I'm at a loss and don't want to burn up my v drive. Thank you in advance!