Lunchb0x

I have an 07 5.4 XLT SC 4wd and if the OD is on and im going about 40-45mph the trans acts like it is slipping and makes a jarring/ clunking noise. Almost like my back tires are hitting spots of ice and then pavement again. Could this be the OD solenoid clip coming apart? Plugs? I am at about 83k miles now

lewissa81

Odds are it's a misfire. That's very common. How old are your plugs?

Lunchb0x

They are the originals. That is what i was leaning towards after reading a few posts here. I have already started putting treatment in my fuel to help with the build up. Looks like I will start there.