2004 Subaru Impreza has a ‘chain slipping’ sound between 1500-2000 rpm’s when shifted from first to second and second to third but never third to fourth. Sound also occurred once when i was (angrily) reversing.
If the noise is heard from under the drivers seat and possibly felt in the floor it is likely the torque splitter. This device allows the front and rear wheels to operate at different speeds when turning while favoring the torque to the front wheels. The lubricant in it is unusual and the friction material used also. Get a good Sube tech to drive the car.
thanks, much, for taking the time to reply to my post. I will get right on it!