I just had my truck in 2 days ago ('05 F-150 with 65k miles) for the slipping / clunking issue and it just had started the chattering vibration from the clutch packs on Monday.
Fluid in the rear end was in pretty bad shape from the clutch pack.
The dealer posted on the repair slip they replaced the clutch packs and per a TSB they lubed the slip yoke as well. Vibrations like a rumble strip were the clutch packs, and the "clunk" on takeoff from an incomplete stop was the slip yoke.
Total cost was $880. I think they see these fairly regularly.
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