Ford F-150 torque converter.

[Hijinx]

Everyone I know who owns one has had to have the torque Converter changed to stop it from shuddering.
Now mine is doing it. Ford doesn't care they get your $2500 dollars for replacing it.

There should be a recall.

 

[Ken King]

Ford recalled a bunch of them in recent years, like 1.5 million F-150s for the torque converter. Check out - https://vinrcl.safercar.gov/vin/ and see if yours has any associated recalls.

 

[Gilligan]

Have you tried the "anti shudder" friction modifier in it? Small tube of that cured the TC "judder" in my daughters Acura MDX.