Exhaust rattle help

Hope someone can help me out here...

I have a slight rattle (metallic sounding) coming from under my truck. I figured out the source of it, if I tap the rubber exhaust hanger on the driver's side, I can hear the sound. It doesn't happen all the time, just went I've been going at highway speeds and slowing down. Can't really hear it with the radio on, but I still want to see if I can fix it. Anyone have any ideas? How do you even tighten that hanger down? I'm thinking maybe clamp it down with a hose clamp or something, but that might make it worse.

Thanks in advance for any help!

Edit: I don't think it's the exhaust hanger anymore, all that stuff checked out.

 

I have that too... I took it to my dealer to check for recalls and TAADAAA there is a recall on the catalytic converter. Apparently there is a component at the inlet that comes loose and rattles. A mechanic friend said that when it gets all the way loose it can block the exhaust and he got to fix other issues that created on a couple of Tacos that did not take advantage of the recall.

 

Do you have a V6? I can't find any info on the recall for my engine. I did narrow the noise down to the catalytic converter on the driver's side. If you tap it with a mallet, you'll hear the spray paint can sound. I replaced the spring bolts on the passenger side, replaced all of the hardware on the catalytic converter heat shield, including the clamp, and that seems to have mitigated the sound for the most part. I can still hear it SLIGHTLY at highway speeds, but it is nowhere near as bad as it was. Still annoying though.

 

That would of been my guess, as I had a similar problem. What solved the problem for me was clamping the heat shield around the catalytic converter, but from your post it sounds like you have that covered.

 

http://www.torquenews.com/1083/toyota-tacoma-catalytic-converter-rattle-warranty-extension

 

He has the 4.0L and not the 2.7L, so the “Special Service Campaign” would not apply to his engine. Toyota is not calling this a recall since the vehicles affected are still close to, or under the warranty. The “Special Service Campaign” affects 2010 to 2014 models. The engine coinciding with the recall is the 2TR-FE 2.7-liter, four-cylinder engine.

 

Yeah, I'm going to take one of those 4" hose clamps and clamp it down. Won't hurt anything, worth a shot. I bought a mechanic's stethoscope and tapped the converter with a mallet and I can hear stuff loose on the inside. Not worth fixing at this point since I'm not getting a CEL, so the cat is still functioning properly.

 

I had the same rattle on mine too. I ended up finding that it was on of the bolts that connects the post cat section of the exhaust. There are 2 bolts that have springs on them and they have a bit of slop in the holes. On mine the hardware was right against the edge of the flange and I just pried it over a little with a screw driver. Rattle gone!

 

What exactly did you pry over? I actually replaced those bolts and the springs since mine were shot.

 

The spring/ bolt were right up against the edge of the flange so I just pried off of the flange so there was a little gap between the bolt and the flange. Didn't have to loosen it either. That solved my annoying rattle problem. Luckily it didn't take me too long to find it. Does this help?

 

No mine is 2.7 4cyl. They replaced the catalytic and all the adjacent bolts, springs, gaskets, etc quiet as can be now. My power even improved (such as it is).

 

Yeah, I think that will help, I tightened those bolts down to ~33 ft lbs when I switched them out. Maybe I just tightened them too much, thanks for your help.

 

I don't think too much... just move them over a little so they're not touching the outer edge of the lip on the flange

 

Well, I replaced the spring bolts (again), tightened everything down, clamped down the catalytic converter heat shield, removed the undercarriage heat shields and cleaned all the debris under there, checked all of the exhaust hangers, connections, the exhaust manifolds, under the hood, the brakes...still can't figure it out. Truck runs fine, no performance issues. There has to be something loose, somewhere, but I can't figure it out. I even bought a ChassisEAR to try and pinpoint it, still no dice. I've taken it to 3 different mechanics and they either "don't hear it", or "can't figure out what it is, but everything looks good".

 

I get a nice rattle because my Catalytic converter is damaged. Although its obvious because I put a golfball sized dent into it. Any possibility yours took a hit?

 

Heat shield on the cat could be loose. The clamp on mine rusted through so I put a hose clamp on it.

 

Who knows -- I don't see any external damage to it, I'm starting to think that could be it, but there's no way to tell until it craps out.

 

Same thing happened to mine, I replaced all the hardware on it and added some extra clamps to keep it from rattling, still didn't resolve the other noise I'm hearing.

 

You could remove your Cat and see what debris shakes loose.