I had some mild shudder before the tune although I never could get it to do it in fifth grear lock up as described. Unfortunately I assumed it was the torque converter. I went ahead and got the tune at about 128k miles. No change in shudder at the time but it has progressively gotten worse.
I can not induce shudder with the throttle except at around 38 or 40 when I believe it is 3rd gear lock up. The slower I accelerate the worse it is but once it starts then I can make it worse by accelerating. Accelerating fast through this point and it just vibrates a little. I have a constant mild vibration after lock up in all gears.
I installed a container of Lucas transmission treatment. This was recommended by a friend that the thicker oil should help if it is a pressure problem and help narrow down that it is something internal. When it is cold the Lucas does seem to help but it was not as definitive as I was hoping it would be to help diagnosis the problem to being an internal transmission issue.
I have severe torque steer from the rear from bad bushings. I am replacing all rear bushings and the rear ball joint. I think this may contribute to some to the vibrations I am getting. I have seen on boards it is possible that the bushings are bad enough to change pinion angles and cause vibrations but I highly doubt that is causing the shudder I am experiencing. They need to be changed anyway so we will see what effect that has on it.
Thanks for the continued help guys. We will get to the bottom of this no matter what it cost me.
