I have a 2008 with the 5.4. I get a shutter/chatter noise when going very slowly (like under 10 mph) and sometimes when backing up. It goes away after a few seconds or when I accelerate lightly. What would be the cause of this? I have 167,000 miles on the truck. It doesn't do it all the time.....just every now and then...

 

does it only do it when the truck is cool?

 

No, does it when it's cold or hot.