Hello I'm new here so I hope I'm posting in the right place. I have a 2005 fx4 super cab with an oscillating vibration that get stronger the faster I go . It starts around 65 mph. I just had the trans rebuilt and the driveshaft replaced due to a u joint letting go at 75 mph. The shop had to replace the trans case and numerous parts. They got a used drive shaft from a wreck and put in new u joints and had it high speed balanced. They can't figure out where the vibration is coming from. They ran it without the shaft on a lift and it still did it. The tires are all new and balanced as well. I was thinking maybe they missed a bad bearing in the trans . I appreciate any help anyone can offer as of right now they are clueless as what to try next as am I.