Rattleing / buzzing sound from under the truck

Hello Ladies and Gentlemen of TW.

I'm having an issue with my 2009 Tacoma. Basically at 1500 RPM I can hear a metallic rattling / buzzing sound from under the drive's side.

The rattle or buzz usually happens in 1st or 2nd gear, since those engage and sometimes drop below 1500 RPM, but with that said, I've been able to replicate the buzzing in neutral revving and holding the throttle around the 1500 mark.

It doesn't happen 100% consistently, and sometimes its louder than others. It is more common when in gear and driving than in neutral.

I did a search on the forum here and as a result tried to see if its the glove box wiring harness rubbing against the metal bracket, but I've taken the glove box off, and for sure the noise is coming from the opposite side.

As far as maintenance, I do regularly scheduled oil changes / maintenance at the dealer, so I'm 100% sure its not because I'm running dry.

I've also asked the dealership to take a look at it when I had my last maintenance check at about 62,000 - 63,000 and they said that its the under engine cover (whatever that part is called, it almost looks like a generic deflection plates / skid plate, but not the cool TRD one) that's causing the rattle because I hit something.

I took the cover off today completely, and went for a ride. The buzzing was still happening, so I can confidently say that it wasn't the cover, even though I did hit debris with it as I do a fair amount of "jeeping" during various hunting seasons.

I want to go back to the dealer and bitch them out now because I twisted one of the bolts off in the process of this and will have to drill out the shaft when I decide to re-install the cover. Those bolts must be cheaply made because there was only surface rust on them, and it gave like it was made out of play dough.

Please let me know what I should look at next to continue to troubleshoot this issue.

 

Sounds like a loose heatshield. Check the exhaust, anything not bolted firmly or loose could do it

 

I have the exact same noise on my 09, I can really hear it when next to a building such as going through a drive-thru.

 

Sounds like heat shield. High temp silicone squeezed in, muffler repair paste or completely remove heat shield (no recommended but that would end the rattle)

 

I've decided to stop chasing this and have the PROs do it for me. I don't have the facilities so I'm at the mercy of sunlight and weather as well as my driveway is pebble so its not a steady surface to be jacking up a 3/4 ton truck over myself.

I've made an appointment for Friday, so I hope some good comes out of it. I still have some mileage left on my 7 year / 70K warranty, so it should be good.

 

If its a loose exhaust component do you guys think it would make the rattle sound at other times, not just when passing specifically 1500 RPM in 1st or 2nd? I'm no mechanic, obviously, but to me this makes sense.

 

I found the problem in my case, it was the foil heat shield above the cat and clamp around the heat shield on the cat. The foil heat shield had corroded and the nuts went on through it. The clamp (see pic) was totally rusted off! I fixed it today, 90 F outside on a crushed stone driveway, ouch !

 

I had that same noise, drove me nuts. It was the shield over the cat, one corner bolt rusted thru and it was the one end of the long skinny heat shield. The hole in the heat shield enlarged and slipped over the bolt. I added a fender washer. Here are the pics of the problem spots.

Edited; forgot pics LOL

 

In my case the dealership guys confirmed heat shield issue as well. They didn't say where, and they said that it looked like I might have hit something or a rock hit there hard enough.

I'm not sure if this is more of the same story from the first time I took it in, but they said they made a modification to it and it was no charge. I accepted. My sanity is slowly returning.

Thanks for all the tips.

 

I have the exact same problem, rusted cat heat shield clamp.

What did you replace it with? A universal fit hose clamp?

It seems that Toyota only sells the heat shield AND clamp as a set. Or am I incorrect?

 

I just used a universal hose clamp I had.

 

I have a theory.
http://youtu.be/dU97w2DH5mc

 

Same clamp doing the same thing on mine as well. These things bust in the same place apparently

 

Subbed...

I have the same problem. I will look into it daylight tomorow.

Thanks for the help, its been bothering me lately.

 

Same problem - 2008 with 100K miles on it. I took it to the mechanic and he quoted $200 fix. I found the problem with a lot of help from your comments and Recker's pics. It was the exact same bolt that Recker is pointing to and it caused an obnoxious rattle around 1500 RPM's. Bought a hose clamp and fixed it for $2. I'm a newbie to the forum and to working on my truck so I just want to point out a few things that I learned that may help others in my shoes: The "heat shield" is actually a casing around the catalytic converter and not the series of thin protectors attached to the undercarriage above the exhaust. See Recker's pic with finger pointing to bolt. This is most likely the culprit if you're having the same issue. I also found that one of the thin protectors had a hole that was rusted and slipped over the bolt. I took this bolt out and added a washer thinking this would solve my rattle. It did not but I'm sure this would have caused a rattle down the line so I'm glad I attacked that as well. Thank you all for your help!

 

Before the emission warranty expires I'd really try to find the problem. I had an old GMC rattle that was a loose baffle plate inside the cat. I wound up trading that in ... but, if I had tried to find the cause sooner, the Cat might have been replaced under the emissions warranty ...

 

I ordered the clamp separately. Part number is 90089-46121 (clamp) and 90080-10096 (bolt). You'll need both unless you use the original (rusted) bolt.

 

Bump for a thanks. Never would have found the rattle in a million years if not for this thread. My case was the same as Recker's; opposite side of the heat shield from the strap. The strap on mine actually looks to be in relatively good condition

 

Awesome!! So glad you got the problem fixed!

 

get a rubber mallet and beat on exhaust, hit the tailpipe that way you don't have to get under truck for now