Hi all,

I currently have a 92 Dakota V6 5 speed 4x4 and it’s started to have this really strange rattle that only happens under specific circumstances. I originally thought it was the muffler as my converter deleted itself and I thought part of it got wedged into the muffler, but after replacing the muffler earlier today the rattle is still there.

It happens on cold starts most often, colder it is outside the worse/longer it rattles. Really only does it around 1100rpm when the rpm’s are dropping, not when they’re rising if I blip the throttle.

It also happens when under moderate throttle at the same 1100ish rpm and will continue to rattle if I hold that rpm.

Also does it around 3k when decelerating/engine braking after heavy throttle and it’s very loud at this point.

Not exactly sure what it could be at this point, I do have shorties on so I’ll check the flange bolts and the header bolts to double check they’re tight, but I feel like if the flanges were loose it would be a constant rattle and I would hear a leak, same goes for the header bolts.

Just looking for places to start checking. In my previous posts I’ve talked about doing a v8 swap but until then I’d like to at least find this rattle as it drives me insane.

Going to try to post some short clips from the interior of the truck as those are the only ones I have as it goes away by the time I can get a video from the outside.

The first clip is around 30mph in 4th gear I believe.

Second I’m not sure but probably about the same.

 

Here is the second clip

 

My hearing sucks, and I can't really hear anything in the videos that I can identify.... Is it a loose heatshield somewhere???

 

Yeah videos aren’t very good and I’m sure uploading then downloading it makes it worse. It does sound like a head shield rattle that’s what I originally thought it was but I looked around and they didn’t seem loose. Banged them all around and nothing seemed like it would cause a rattle.

Granted with it being a rattle at specific rpm’s it makes me think it’s a resonance issue which could be making a heat shield rattle against the body somewhere.

Though when I got under it the other day and figured it was the muffler, the rattle sounded like it was coming from the muffler and it sounded very much so like the muffler was the source.

Guess I could remove all the shields I can find and see if that’s the issue and go from there lol.

 

I finally found the issue, and it was a strange one... I unbolted all of the heat shields running along the bottom of the cab/firewall on the passenger side. Rattle was still there. Got under the truck to try to get access to the header flange bolts and noticed a weird shield riveted to the driver side y pipe that was sitting about an 1/8th of an inch from the pipe. Figured, what the hell, and bent it away. Didn't end up checking the flange bolts but it seems like that rattle went away, kind of weird for that to be causing a rattle as it was an 1/8th of an inch away from the pipe, unless it was something with the contact between the two thin metal surfaces touching where the rivet went through.

 

None of us here would of had a chance to guess that right.

 

Haha yeah I still don't really know what the purpose of it is. After I took the bolted shields off the passenger side and it didn't stop the rattle I was like guess I have to deal with this until I pull the motor, last thing I expected was me bending some random piece of sheet metal a quarter of an inch was going to fix my problem

 

For anyone curious, here is an image I found on google actually from the forum somewhere. It's that little shield thing right above the front drive shaft. In this image his is bent away like mine currently is, but mine was about 1/8 of an inch away from the pipe which was somehow causing a rattle. Not sure what the purpose of this shield is as if you look at any aftermarket y pipes they don't have any, but there's my solution to a problem I think I'm the only one having lol