2001 F150 with 115K on it. 5.4L, Automatic Trans. Serviced every 15K, company policy. Noticed this week that while driving up slight inclines (on the highway) and with light pedal pressure, the truck seems to hesitate, almost a thump feeling and then catches and will repeat if the same operating conditions continue, though not as regular events or regular intervals. Almost as though the tranny "Slips" and catches. Doesn't feel like the engine is doing it. Any thoughts guys?

 

My truck is doing the same thing, so I started a search this thread came up with no responses from 2004! Damn! I was wondering what is causing this.

 

Engine misfire. It's very common on these engines, usually a bad ignition coil.

 

Well, I'll start there. Thanks for the reply.