Can anyone help with diagnosing this issue with my 2010 STX 4.6 2valve with the 4r75 tranny, when I'm at a stop and accelerate the truck feels like I'm going over rumble strips thru first gear, once im into 2nd and beyond it rides smooth. I've been reading that it could be the torque converter making the shudder, maybe the slip yoke, or the slip bump. Just not sure which, has anyone had this issue if so what's the remedy? Thanks!