Engine/Transmission (1998.5 - 2002) Annoying rattle coming from underneath

[PatrickCampbell]

I have this very annoying and embarassing rattle coming from underneath the truck. It sounds like metal rattling on metal, like a heat shield or something but I don't have one. The exhaust is not hitting anywhere.



I can't hear it when I am driving but it is VERY present when I am slowing down, coming to a light, driving around in a parking lot, etc. It goes away completely when I stop so I can't leave the engine running and look underneath to really figure out where it is coming from.



It seemed to have started happening when I had my SBC Con OFE clutch put in (did not do it myself). Any ideas?

 

[AndyJohnson]

There is a exhaust shield right there that either bolts on your exhaust or on the cab. This has the 4-wd actuator lines connected to it and usually gets removed when doing clutch. And if the one bolt isn't put back in it rattles but looking at it you would never guess that is your problem but it was on mine. Same exact thing as u described.

 

[Holysmokes]

Im not sure if this helps or not. I have a 2000 and it did the same thing. I hunted and hunted for it couldnt find it. Then, when I had someone ride passenger, they could FEEL the rattel under their feet. Especially going over RR tracks. Turns out I had a broke shock bolt on the passenger side. It needed new shocks anyways. FWIW a buddy of mine came across the same thing in another truck.

 

[PatrickCampbell]

The only thing I see is a very large "soft" heat shield that covers the firewall and a little bit of the underbody. It is not entirely tight but again it is soft, not metal so I don't know that it would make noise. I might have to get it up on a lift because it is killing me. Checked the shocks and they are pretty tight.

 

[PatrickCampbell]

Haha well



I actually went over to Meineke to get it up on the lift.



The exhaust was a little lose but it wasn't rattling. The guy welded that up for me since I have it pointing down after the cab.



One of my shocks that I had felt and previously recognized as being a TINY bit lose seemed to have been it.



I felt it before and thought Nah that can't be it. I guess when a something is a LITTLE lose, a 4500 pound knocking engine can make it rattle a lot

 

[Fred Swanson]

Patrick, loose, as in the mounting, or the shock body itself?

 

[PatrickCampbell]

It was just the lower shock mount from what I could tell. I had installed the new shocks just a few weeks before the clutch. Guess I didn't do it tight enough and it loosened up a little over time. Thanks for the follow up