4r100 swap 2002 into a to a 2000 problem

[jonesn619]

I have a 2000 F350 7.3 4x4 CCLB. I put a 4r100 out of a 2002 the tranny was working great when pulled. But now it holds 1st gear a little to long then when it shifts to 2nd gear, the od light starts blinking. It drive great after that, but light blinks. The fluid is clean, dose not heat up, shifts good. I have taken the truck to several trans shops and ford, no one finds a code. But they all want to take my money. any suggestions. thanks

[Jarrod B]

shift solenoid im guessin.

[jonesn619]

Okay, that is what I was thinking, just wanted to see if anyone else had this problem before I go replacing parts. Thank you!