I bought this truck several years ago and the problem seems to be getting worse. When I sit in park or neutral and rev the engine, sounds normal, but when I start to drive, there is a whining noise just before it shifts from lo to 2nd and then again from 2nd to high. the whining stops once it shifts it is just when it reaches the point just before the need to shift into a higher gear. could it be the torque converter?

 

Have you checked or changed the fluid recently?

 

I have kept a close eye on the fluid level and have changed the tranny fluid out twice since this has started. replaced the filter and fully flushed the system both times with no change.