Misfire or transmission?

[2x_tom]

I have a 2014 with 112k on it I bought last year with 101k. I’m unsure of the maintenance history as I bought it from a police department. It is a regular XLT that never had lights or sirens in it. I assume being a large department they had a decent fleet maintenance program but who knows.

This week I went on a 1200 mile trip and it felt like while driving over long steep grades at highway speed (45-60) the truck would almost drop out of gear and go right back in momenterially. Putting it in tow/haul greatly reduces or eliminates the issue.

I just pulled the codes with Forscan lite (no laptop). It shows a minor misfire. Would that cause this? Should I just do plugs to start or is their more I should be doing? Also any advice on the plugs? The look straightforward enough. Do they still like to snap off in the head or did ford fix this by 2014?

Anything else I should be looking at?

Thanks for any advice.

 

[2x_tom]

Well I’m hoping I answered my own question. I drove around until it did it, immediately pulled over and pulled the codes. Sure enough it shows 2 misfires for the cycle. Next I drove around a bit, babying it and trying not to have it do it. Just pulled the code and no misfires.

So now I have to figure out what the misfire is about and hopefully that resolves it.

 

[2x_tom]

Pulled #5(left) and #8 (right) so far. I guess they are original plugs and had to be done either way.

 

[Trainmaster]

Change the plugs. Common problem. Feels like the transmission. No need to worry' they're normal plugs.

 

[smith]

Just had the same thing. Thought it was transmission or COP but turned out to be plugs.