To Caller with F150 with rattle/clanking under trucking during acceleration

The caller said a sounded like she was pulling cans behind her truck resonted from under her truck when she acclerated, but when she coasted the noise went away.



Tom and Ray gave a final answer to this caller of “take it in it could be serious” and had suggested possibly a driveshaft problem.



From the caller description my first guess is heat shield. A diagnosis I’ve heard Tom and Ray make many times. Under acceleration the engine vibration shakes the exhaust enough to get the shiled to rattle…but when she is off the gas the engine returns to a smooth idel rpm…no more heat shield rattle. The thin/tinny heat shield metal rattling against the heavier exhaust pipe metal would sound very similar to a tin can rattling.



What is everyone else’s thoughts?

I was thinking of a rock in the hubcaps.

I was wondering whether the spare tire carrier underneath the truck was knocking around without benefit of a spare. I am always amazed by how many pickups I see with empty spare tire carriers knocking around underneath the bed.

Both good outside the box ideas, but she said it only occured when the engine was under acceleration, not coasting and it seems that rocks in the hub caps and a loose tire carrier would both cause clanking/noises anytime the truck went over some bad roads or bumps and not be so consitent when engine was under power.

The thought about a rattling heat sheild sounds logical to me.