maybe a loose heat shield for the rattle?

 

hmm I will take a look at that, but why would it go away after ~5 minutes? And it only makes the sound when in motion-and at that mainly only in drive... if it were a rattle shouldn't it do it if I rev the engine in neutral?

 

Could be the brake rotors got rusty--mine do if I don't drive it for a day and then they are noisy for a short time. Also check to see if you have a piece of gravel stuck between the dust shield and the rotor.

 

possibly a rock behind the rotor shield. they can be elusive as they bounce around in there and sometimes get where they are touching the rotor and sometimes not. I had it once and the local buy bent the shield out just a little so that there was more space on the bottom than the top, so that in theory if the rock got in, it can easily fall out.

 

hmm I will take a look at that, but why would it go away after ~5 minutes? And it only makes the sound when in motion-and at that mainly only in drive... if it were a rattle shouldn't it do it if I rev the engine in neutral?

Its really hard to diag noises over keyboards unless it is a common complaint. But it could be a heat shield that is heating up and expanding overtime to change the inference for the rattle. And when you shift into neutral, the NVH(noise, vibration, or harmonics) is changed. Or as mentioned, it could be a stone within the brake system.

But that you also smell "used oil" is not common to either of the above-mentioned issues. By saying "used oil-smell" do you mean a "burnt oil smell"? If yes, I'll venture other possible issues: you have a rear wheel bearing starting to go, or a problem with the rear differential. Both can cause intermitten rear noises when first starting to fail.

So all of the above are potential areas to inspect.

I think the OP has a valid issue as a "dragging tin cans noise" is not normal. But I wonder how many of the recently started drivetrain/mechanical topics are some Rav4 owners being hypersensitive to any perceived-drivetrain abnormality due to the recent focus on the recalls? IMHO, I'd bet many are driving with no radio on for the first time ever, trying to listen/feel for any potential issues. :shock:

 

I had heard of the rock on the rotor shield and tried to check that but didn't find anything.... I still haven't had a chance to go under and check the heat shield. I will do that this week hopefully as it was making the sound again today after being parked outside for a day in below freezing temps...

I had kind of thought about the whole NVH thing too, but I guess I should have mentioned I have it in drive and hold it with the break and it doesn't do it unless i start idling/ accelerating forward, which probably means it is something that moves only when the wheels move.

When I say 'used oil' I guess I have never really smelled 'burnt oil' to tell the difference, but i mean that smell oil gets normally at ~4-5k miles of use-right before an oil change. Does burnt oil have a similar smell?

Since it is so cold around here I may end up leaving it at my dealer overnight since they tend to be very good. I will let you guys know what I/ they can figure out.

I do agree with you about the hypersensitivity, but I heard this noise with my radio on at a 'normal' volume (probably between 10 and 20 on the JBL) and I surely would have noticed it before sometime I didn't have the radio on. I do totally agree about a lot of other issues though. If I record the sound sometime are we able to upload sound files to the forum?

 

Check diff ans transfer oil levels.

 

Thanks for all the responses everyone! This weekend I finally got a chance to take a close look at everything. It ended up there was a stone stuck between the rotor shield and the rotor on the rear right tire. Problem solved!

 

glad to hear it :wink:

 

Yes, that's great to hear...and a much cheaper fix that all our other ideas. :cheers:

 

Thanks for all the responses everyone! This weekend I finally got a chance to take a close look at everything. It ended up there was a stone stuck between the rotor shield and the rotor on the rear right tire. Problem solved!

That is good news. My Subaru used to have that happen at least once or twice per winter, when the roads are sanded with gravel that's just the right size to get stuck. The noise scared the heck out of me the first time it happened!

It always happened to my front brakes, so I used to handle it by going to an empty parking lot near my house that had a bit of rough pavement. I'd sverve around the lot, making sure to always hit the rough pavement until the stone rattled itself out. Never took me more than a minute or two.

 

Thanks for all the responses everyone! This weekend I finally got a chance to take a close look at everything. It ended up there was a stone stuck between the rotor shield and the rotor on the rear right tire. Problem solved!

Thanks! This kind of info can benefit many people.