I have a 2002 f150 fx4 with 114k mi. It has started to shudder really badly at about 50mph. Could this be the torque converter?

 

mine does the same thing. does it happen when it shifts down into the last gear(overdrive gear)?

 

Have you ever changed the tranny fluid? What about the spark plugs and coils?

 

https://www.f150online.com/forums/tr...n-shutter.html

good luck

 

I can not be sure from the vague description, but I have had shuddering develop between 55-70 mph due to a bubble in the tire

Worth a look.

 

Does it shutter when it first shifts into overdrive and the RPM's drop? Mine was doing that but wouldn't throw a code. I changed tranny fluid and it didn't help at all so I changed the COP's and the truck ran like brand new again. I would start with COP's from ebay, alot cheaper than starting to play with the tranny.