Acceleration Rattle

So to start off I have a 2008 V6 with about 217000km on it, recently I’ve noticed a rattling noise at exactly 2000rpm when accelerating and only at that rpm (not above or below) and only when driving, it doesn’t make the noise in park and neutral. Sounds to be coming from the outside of the vehicle under the passenger floorboard or under the passenger seat, hard to tell. Anyway I’ve already checked all the heat shields and tightened them where need but the noise is still there. There’s a number of things I think it could be including an exhaust leak at the flange for the tailpipe, engine pinging (just because of what I’ve read here on TW) or one of the cats is going bad. I don’t think it’s pinging as it’s coming from under the truck and I just did the spark plugs, cleaned the MAF and it also doesn’t do it at a range of rpm only one specific rpm. I have an empty tank right now so I’m going to fill up with a higher octane tomorrow to rule pinging out. I would love to get some thoughts on this noise before I give up and take it to a shop.

 

Interested myself, I have this same issue in my 06 manual 4cyl.

Mine is strictly at 1600 rpm though.

I'm starting to think carrier bearing.

 

Sorry haven't been on here in a while. Hopefully you got your issue figured out, carrier barring could be a possibility, mine was squeaking when it went bad. For me the rattle ended up being caused by a bad donut gasket for the exhaust flange, changed it out today and the noise was gone.

 

Good to know, was it the donut in front of the cat tube or after?

 

After, it was the joint where the pipe from the cats meets the pipe going to the muffler. I do have an after market exhaust and I’m not sure if the stock exhaust just has a typical o ring style gasket or a donut gasket. You can always bang on the exhaust with a rubber mallet or your hand and listen to it at that joint, that’s how I found it on mine, mine made a fairly loud clanking sound at the flange then when I took it apart the gasket pretty much crumbled in my hands. I also noticed after about a month of rattling it began making a faint clanking/rattle noise over bigger bumps

 

Thanks! I will have to look into this, maybe the aftermarket gaskets that came with my CAT are not very good quality.

 

Recently had this on my 2008 4.0l. I filled up with BP 93 and added the Berryman B12 cleaner and haven't heard it again yet.

 

2005 Tacoma with 174K miles. I have noticed the same thing. I have read that there some check points to see and inspect. Information from my Hayes repair manual for 2005-2009 Tacoma's. At certain miles, maintenance is required, and one is to check the drivetrain. So, I did just that, and amazingly I found one of the bolts on the driveshaft to the rear differential was loose. I mean it was only finger tight. So pulled out the torque wrench and retightened. Also, some of the zip ties for wiring harnesses and other components were loose or broken off. One rattle and this was stupid, was my back seatbelts were rattling against the interior body panels.
Still going through the truck looking for other rattling noises. One note said it may be possible to have loose engine mounts. Ugh! I hope not, but when I inspect the mounts, I don't see any wear or tear on the mounts. I'm still looking for more possible rattling noises. I do have the MAP spray so I will be cleaning it.

 

Oh also check the little screws that keep the air intake plastic attached across the engine bay. Those will cause problems.

 

I found the rattle! After crawling under the truck and feeling around the trans, engine bay and all the way to the rear end, I had tapped the plastic shield on my front left tire and found the shield had lost a couple of its snaps to hold it to the trucks frame. The small plastic shield between the tires fender well and the engine.
Did a quick test run, and done! No more rattling. Now I' still dealing with the VSS Sensor A. It is hampering the use of the cruise control.

 

Nice find!!! Those ones can be extremely difficult!

 

it drove me nuts and I found purely by accident. Just brushing my hand up against it, helped me discover that was the problem.