2010 V8 tinny rattle under acceleration

[Mozambique]

So, recently my 2010 V8 with 210k km had developed a tinny rattle sound mainly evident under acceleration. It sounds like a rotor dust shield rubbing, or a loose heat shield. I wondered about exhaust muffler baffles being loose, but no noise when revving in neutral. I haven't had a chance to have a good look underneath yet, but was wondering if this rang any bells?

 

[scapistron]

Have you already addressed the heat shield under the transmission?

 

[Mozambique]

Ha!
No, need to check obvs things when I am back from vacation

 

[Mozambique]

Ha!
Never guess what it was.
The pipe coming rearward out of the middle muffler has a flange on it where it goes it to a flex pipe. The flange had rusted through leaving a loose metal ring encircling the pipe. On acceleration it was bouncing around. I snapped it off using pliers. Annoying rattle solved!

 

[Mozambique]

Hhhmmm....... thought the noise had gone away, it hasn't. All heat shields seem secure.

 

[jlglr4]

The transmission heat shield bracket is a common problem. Mine has cracked three times (although I repair it with a welder and I’m a terrible, terrible welder).

It will feel secure when you try to move it, but it’s the bracket underneath that develops a crack and will vibrate when the tranny is under load. Take a mallet and rap on it a few times under the car. If it’s cracked, it will start to vibrate a little and make that tinny rattle sound you’re hearing.

 

[Mozambique]

Found the issue!
First hint was a silver band around the drive shaft (front to rear). Turns out the rubber diaphragm through which the driveshaft passes through at mid-way point had a tear in it. When accelerating it was moving and rubbing against a bracket. Quick fix was using construction glue to seal the tear.
Have an Amazon $CAD299 replacement drive shaft ready to go on. Simple unbolt and replace. Will see how long it lasts.
Ditto got a $CAD 99 replacement front wheel bearing hub from Amazon (both items A-Premium brand). It's a 6lb lump of metal for $99??? Ditto, will be interesting to see how long it lasts vs. $270 aftermarket one also of unknown quality.

 

[scapistron]

Bolts at the transfer case and rear diff are supposed to be single use. Although I don't think they're actually torque to yield. If you're reusing the original stuff be liberal with the blue loctite.

 

[Mozambique]

Yes.....$63 from dealer