ok i have a 2008 f150 4x4 5.4 crew cab. this dose not happen all the time but when taking off and the truck shifts from 1st to 2nd gear i get a clunk or as i told the dealer its almost like you run over a stick in the road. would like to get this fixed before the warrenty is up but they said wait for it to do it all the time and the bring it out. anyone else have this problem or know what it might be?

 

My 06 does this but its more of a grind then clunk almost like the trans slips then the gears grab. Very loud and noticeable but only does it randomly. Not sure what it could be. I was told it could be the rear end or the flex plate in the transmission. Could also be from the towing I do everyday and that the trans cant hold up to my demands. Hope we can find out what is causing this.