Just wondering if any of you guys have had to deal with this. When cruising around 50mph, with a light acceleration the torque converter kicks out and it feels like you ran over a washboard. It may just thump sometimes. about 30k miles back I had the thump only. I changed the fluid and added BG conditioner and the thump went away after a few miles. Im thinking I may need to replace the converter? Im a 30yr exp ASE master tech but I don't have much domestic experience. Oh yea this is an 02 S'crew 4x4 5.4

 

TC chatter. If its been doing it for 30k its time for new converter. The trans conditioner for the Ford transmission wont help at this point.

 

Thanks Carcrazygts2, but what I meant was 30k miles back I started noticing a thump when the converter disengaged. I flushed the trans and added conditioner. after several miles the problem was gone. Now 30k later I stared feeling the thump again and progressed rapidly to the washboard shutter.

 

You can try doing a just a fluid exchange and try this additive. It would be cheaper than a TC. In the past once it got to the hard shudder its almost impossible to get rid of it.

Here is a link to the stuff to try with fresh fluid. You may need 2 bottles.
http://www.lubegard.com/~/C-250/Dr.+...t+Shudder+Fixx

 

I have the same thing in my truck, it happens between 3rd and 4th gear. Going up hill is what makes mine do the shutter, if I am on a flat road, or going down hill it shifts fine, but on a hill it shutters. It was diagnosed as a bad torque converter (though my mom still thinks it is an O ring that snapped and it in between the gears). Since it sounds like it is beyond the point of repair (I have driven 13k miles like this, idk what previous owner did), does this mean all I need is a new torque converter? Or a whole new trans? What will happen if one day going down the road my torque converter decides to say screw it and gives out?

 

The shudder is caused by the clutch inside the TC. Eventually when the tc slip reaches 100% it will no longer lock. Causing the trans temps to shoot well past 200*. Every 10* above 135* takes about 10k miles off the transmissions life. So prolonged driving with a slipping converter will eventually cause the transmission to slip and need to be rebuit.

 

I almost bought a 2007 that had that issue. At a certain speed it'd thump like that. Turns out the torque converter was ready to go at any time. The repair was looking to be around $2000 on that truck. Hopefully it's not at that point for you, but if it is, get it does as soon as you can before it does more damage