2000 f150 4.2L 4x4. I decided to take my truck to the tranny shop. I was having a hard 1-2 upshift and the o/d off light was flashing. It almost feels as if there is a slight delay before shifting into 2nd and then it will bang into gear. All the other shifts are good. They could not find any codes and they said the hard shift 1-2 shift is caused by a bad torque convertor?? Does this sound at all possible?? they also said my speedometer was about 4-5 mph fast.

 

No I call BS I dunno what the problem is but I can tell you it isn't the converter

 

Yes, it's possible.

If the computer detects a problem with the torque converter it will put the trans into limphome mode. In this mode the pressures are elevated and that will cause a harsh 1-2 shift.

 

The only code the converter can set is lockup slippage. If that happens rarely will it put the pcm in limp mode it would have to be really bad and the problem would have been noticeable as a terrible shudder in high gear for a long time before that.
Alan