LB7: Mysterious Rattle

[jbstephenson]

Hey guys, sorry this post is going to be a little vague but I'm trying to get all the help I can. I've got 2 mysterious rattling sounds coming from under the truck. One sound like metal on metal, rattles when I go over bumps, etc. but if I apply a little bit of pressure to the brakes and to over the same bumps, etc. there is no rattling. The second sound is more a knocking, I can't really tell what might be going on but it rattles when I hit rough spots in the road, brakes don't affect the sound. These have both been going on for a while and continued after I did my front end this summer. Anybody run into similar problems or have any suggestions for things I might look at? Thanks

 

[blue09dmaxx]

Traction bars? Torsion drop bracket?

 

[jbstephenson]

Traction bars? Torsion drop bracket?

Don't have traction bars, will have to check the drop bracket tomorrow though

 

[kiwilml]

Knocking sound like coming from steering shaft area?

 

[Howeskier]

Mysterious Rattles

I have owned a few post 2000 chevy 3/4 tons and the rattle that goes away when you apply light pressure to the brakes is the front brake pads rattling. The pads last forever but the metal ends of the pads that slide no the calipers gets worn out and allows the pads to rattle you can replace the tin pieces on the caliper brackets which will help for a while, but best bet is to replace the pads. Drove we crazy on the 2000 model and then I figured it out. Not sure about your other rattle. Good Luck!

 

[TheBac]

Knocking sound like coming from steering shaft area?

This gets my vote for the knock.

Howeskier is right on the rattle.

 

[jbstephenson]

This gets my vote for the knock.

Howeskier is right on the rattle.

It could be I honestly haven't paid as much attention as I probably should. Is it the shaft itself that is rattling, or a bracket or something like that

 

[Budneeds2beers]

Carrier bearing? Mine would clunk around on bumps or hard breaking. How about exhaust? Pipe rattle broken hanger? How are control arm bushings? Maybe ones gone and your getting sloppy metal on metal...

 

[TheBac]

It could be I honestly haven't paid as much attention as I probably should. Is it the shaft itself that is rattling, or a bracket or something like that

Look at the plastic "bearing" at the bottom of the steering column, before the intermediate shaft. Makes a nasty clunk when it fails. How do you not know about that? Its extremely common.

I would also check the torsion bar mount ends -- the rubber bushings do fail. Budbeers has some good ideas, too.