Anyone ever notice a very subtle knock coming from the undercarriage when driving slowly and making a turn or going over bumpy surfaces? I seen a Facebook post were someone with a similar issue had their exhaust come loose. I checked under my truck today and couldn't find anything. Just wondering if this was common.

 

Haven't heard any personally. Pretty hard to trace but id be shaking everything.

Helping ya out with a *bump* to the top for a fellow aircraft mechanic.

 

 

 

Check your passenger side seat belt...mine rattled against the B pillar on bumpy roads.

 

Thanks guys, I'll take a look at this stuff today. It doesn't sound like it's inside the cab but can never tell. The dealer I use is 30-40 miles away and don't want to take it to them just so they can tell me they can't hear it.

 

So I bounced on the bumper trying to duplicate the noise. The only noise I got was from my 5/8" shackles on the hitch for trailer chains. I removed them and couldn't hear anything else. Been driving for a couple days now without them and it seems to have been what was causing it. I've had them on there for quite a while now, I don't know how I never heard them before.

 

Last thing I'd mention is if you had a spray-in liner done and they removed your bed-bolts, this will cause a creaking / cracking / knocking sound when going over bumps or uneven roadways. It's not really that subtle though.

 

Check your exhaust filter status to see if you were going through a regen. My truck made these same noises which was baffling as this truck has been dead-quite and completely dependable. Checked my filter status and sure enough, it was going down. By the time i got home it had only gotten down to about 80%. When using the truck the next day, dead-quite again as the truck was no longer in regen mode.
I hope this was your "problem"!

 

Well apparently it was just coincidental that I didn't hear it after removing the shackles. A little later I began hearing it again. So I finally had a chance to make an appointment with the dealer. I was expecting them to claim they didn't hear anything but that is not the case. They said they hear it very clearly, problem is they can't identify it. So in the waiting room, I sit...

 

Same issue here on a '18 250. Mine sounds like its coming from the front left somewhere in the suspension/steering linkage as its most apparent during low speed turns (think pulling in the driveway or a parking space...). The most similar thing I can think of to describe it as is when you are in 4WD but on a paved surface with wheels turned; that *clunk *clunk *clunk you get. Best of luck and I'll shout if i figure mine out!

 

They said they couldn't find anything loose so the next step is to start taking it apart piece by piece until they find something worn and try to duplicate it with the parts removed that still allow it to be driveable. They have narrowed it down to being in the front end.

 

"Nope... I still hear it..."

 

 

Haha hopefully it doesn't go to that extent.