ford that shift hard 1999 f 150
standard or automatic?????????????????
like Kelly asked auto or stick? Assuming auto,Which engine and are there any diagnostic codes, O/D light flashing, not coming on, or staying on all the time? If it doesn't have some kind of shift kit in it that's not a good thing. If it's an internal trans problem and not a mount or something moving excessively in the drivetrain harsh shifts are usually due to high line pressure for 1 reason or another, sensors, solenoids, it goes fron very small to real big. Just need more info.
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