I have a 2007 f150 king ranch. While towing a boat (4500 lbs) I noticed and intermittent rattling. I can occasionally manipulate it with the gas pedal but not always. This only happens while towing. It almost sounds like a can rattling underneath the truck (see attached video). I took into a shop and had them change out the trans fluid as I believed it was due anyway but that did not fix he issue. In addition they checked out the under carriage and nothing looked abnormal.

Any thoughts?

 

Is the exhaust system intact? Sounds almost like a pipe hitting the frame when the truck is under load.

 

Man,

That sounds a lot like the sound I was getting from a bad VCT Solenoid I got from NAPA straight out the box.

It got worse the more load that was placed on the engine. Kind of like an electric rattle sound.

does it seem to be coming from under the hood? Not saying thats the problem at all, just a similar sound that may be worth checking.

 

Thank for the response. Sounds like its coming from under the floor boards, hard to tell though. I may try to mount a camera underneath the next time I pick up the boat.

 

The shop I took it to said everything underneath looked good. Im thinking about a duel exhaust so when I install that I can verify the stock exhaust.