PWM Three Phases with PIC
The PWM module in the PIC18 that produces 3-phase PWM is not called a Timer. It is called the Enhanced Capture/Compare PWM module (EECP). It is not a timer, but uses the one of the other timers.

There seems to be conflicting info about when the ECCP's features (even if the ECCP itself might not be) are present on 28-pin devices: