Torque Converter Issues

[HellzMindPlaya]

I have read quite a few threads about the issues BMWs have with their torque converters in relation to the X5 and I am pretty sure I am having some sort off issue with the converter in my 2003 4.4i. (LH40078 I think if anyone needs any more details!) Between the speeds of maybe 30~35 MPH all the way up to just before the torque converter locks at 60 MPH I have a strange shuttering issue. The torque converter locks just fine once I hit 60 and i no longer have any sort of studdering (until I slow back down below 60 and then the shuddering begins again). I have read that one fix is to use Instant Shudder Fixx By Dr. Tranny (Lubegard) and it seems like everything I read said that the earlier you got that stuff in the transmission the longer it kept issues at bay...

So my question is - For anyone who has used the Instant Shudder Fixx - was your torque converter still locking up at 60 before you used the Instant Shudder Fixx, or was it locking and unlocking (shuddering) at all speeds? I am wondering if I have a different issue because my torque converter works as it is supposed to above 60 (at full lockup) but only shudders at lower speeds.

If anyone has had experience with this I would love input. I am planning on adding 2 tube of the Instant Shudder Fix, but if I instead have an issue with a PWM solenoid valve or something valve body related and one of those need replaced I would rather just do that.