I have a 98 4.6L F150 4X4 w/about 105k miles. It just recently started vibrating when it shifts into overdrive. It also does it just before downshifting if I'm going up a hill, etc. The truck is in great shape, but I can't figure this one out. Anyone ever had this problem and/or can help?

Thanks in advance

 

I would take a look at the TPS.

Or simply pull codes