Question; I have 2017 Lariat 5.0 with 173000 on her. Recently at low speed or when I’m speeding up there’s a noticeable bump I’m noticing. Like it’s misfiring but without the backfire. I’m religious about maintenance using only amsoil in everything. Could it be a spark plug or coil pack? The timing chain was changed at 100k (dern that wasn’t cheap). Any ideas would be great to hear. Also has the 6 speed which I’ll be doing fluid flush at 175k, last done at 110k. Everything is original with no issues ever except this now.

 

That's not much to go on. Can you describe the bump in more detail? Is it metallic in nature? Is it a low thud? Is it coming from the right, left, front, back? Are you able to recreate it at will? If so, what do you do that causes it?

 

A single bump while accelerating from a stop could be caused by the slip yoke needing to be greased.

 

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When you step down on Throttle, is the 'bump' on a down shift?
Misfires don't 'usually' cause a Backfire There is no Spark or Fuel on a Misfires.
Backfire is the loud sound of fuel being ignited with either an Intake Valve open or an Exhaust Valve open.
Need further info to get a clue.
Scanner Live Data might be a help in detecting any cause with the engine.
Good luck.