4 speed 1-2 shift clunk

[Engineer]

Hi Guys,

My Au 2 XR8 on the odd occasion will get vey rough on the 1-2 shift. It happens at light throttle applications and it feels as if the car is not going anywhere when it is about to thump into 2nd. I understand this is a problem with the 4 speed auto and there is a ford ecu software flash that supposedly fixes it.

It is very annoying as it is a fair thump in the driveline when it occurs. I am reluctant to get ford to flash the ecu before I know what the story is.

Could anyone out there shed some light on this if they have the issue or if they have the solution.

Cheers
Engineer