Except for your comment on the rubber being thinner on the bottom and the effect that may have on transmitting vibration to the body I agree on the bad driveshaft. It may be out of balance somehow even with few signs of wear.

BTW, since the drvieshaft is permanently geared to the front differential it will turn anytime the front wheels do, neutral or not.

 

Just crawled out from under our '06 4WD with 148,000 miles after checking that the four nuts on each end of the driveshaft were tight.
(I had the driveshaft out when replacing the whole rear K-frame and have been having a single clunk from under the center of the car after the it's parked overnight. The clunk goes away upon disconnecting the 4WD ECU.)
Anyway all eight nuts were tight. There was the slightest play between the front and rear sections of the shaft but I'm gonna leave it for now.
I saw what you mean about the rubber bushing on the center bearing mount. Mine was slightly squashed too but I left it as is. It did appear it was designed to be flipped over and remounted with the top side down for longer life I suppose.

 

Thank you for the replies! The driveshaft is laying on my garage floor, so I went out to take pics of the center bearing to post here, and discovered something I had missed.
Video below is the front ujoint, which is slightly stiff but otherwise works as it should, rotates both directions:
front good u-joint video

The back one looks bad, it only turns the one direction, the other direction is frozen:
rear bad u-joint

The center rubber seems like it has a lot of play in it, I will see how it compares to the new one that's incoming. Just out of curiosity I did flip the entire driveshaft over 180 degrees, and it sits much better now in the center rubber piece.

Also, that clunk you get, could it be a rear differential mount going bad?

 

Your noise is probably that rear U-joint being forced to rotate against it's will. Where'd you source the new shaft?
In previous threads issues with the driveshaft U-joints have come up with it being noted one had to replace the whole shaft when "normally" just the U-joints themselves could be changed. Driveshaft Noise - Replace drive shaft and support bearing?

Altho I did have to move my rear differential from the old K-frame to the replacement one, the mounts were good so I doubt it's loose. In an effort to locate the clunk about a month ago I had the car on four jack stands and checked every nut and bolt for tightness that I'd removed during the K-frame job.

My clunk is more of a pronounced click and definitely from under the center of the car not the rear. But then after initially moving the car first thing I can't duplicate the noise.

One option for me is leaving the 4WD ECU unplugged during the summer but with the V6 that creates easy front wheel spin on takeoff with any amount of throttle. That's either fun or not depending if my wife's riding shotgun.

 

Got it from rockauto with the 5% discount, and yeah the entire shaft. Just under $400 when all is said and done. (I didn't get the economy one)
My driveshaft never once made any kind of clunk or clicking noise. Just god awful rumble strips at first. I thought about a driveshaft shop, but the center support bearing seems a little wonky as well, who knows maybe that's normal but when I get the new one in I'll compare.

Does that click happen when you put it in gear and load things up or when the wheels move?

 

Got it from rockauto with the 5% discount, and yeah the entire shaft. Just under $400 when all is said and done. (I didn't get the economy one)

Does that click happen when you put it in gear and load things up or when the wheels move?

That's a great price and it's good to support one of the forums sponsors. I've bought parts for almost all of my vehicles from them.

The noise doesn't happen until you move the car maybe 10-15 feet and then only after parked at least overnight and only once a day. My first thought was the rear brake pads moving a little since it always seemed to be on a change of direction after the car was parked. But with the 4WD being disabled by unplugging the ECU "curing" the noise it has to be driveshaft related.

A little more 4WD info: While I was investigating a way to keep the rear drive engaged above the 25 mph where the Lock button disengages, I mounted a LED in the lower dash and connected it to the drive signal going to the electro-coupler. I also added a switch and a diode isolated power resistor to send 3A to lock the coupler. It did work but made the 4WD error light flash so I ended the project. With the LED still connected I noticed the coupler is getting near full power ASA the car is shifted into any gear.

Since my wife says it always happened when she was turning I should probably plug the ECU back in and watch the LED to see if the drive is being removed because the front and rear wheels are going different speeds on a tight turn. Another option is to connect the switch to enable or disable the 4WD depending on who's driving.

 

My first thought was parking brake related, but I'm sure you already thought of that since you mentioned brakes. If it were my vehicle I would line up a bunch of tests to run to try and narrow it down. After sitting for the night, and getting itself into "clunk mode". And once it clunks you are done testing for the day...so this may take a while

• start vehicle up and let run for a few minutes just sitting there, does it still clunk
• will it clunk when you just start driving only going one direction. (ie don't back up and then go forward etc)
• start it up, and then shift back and forth into reverse, drive, but waiting like 30 seconds between shifting, this all happens just sitting there where you parked it.
• start it up, and immediately put it into 4 wd, then drive.
• does it happen at certain rpm or mph?
• start driving in a certain gear each time, to see if transmission shifting causes it. ie shift into 1st and just drive until you get a clunk or enough time goes by.
• would be nice to see if it would happen in neutral as well. if only you had a small incline to park on overnight.

Did you do the slow turning in a parking lot, turning steering wheel stop to stop, the way you check your front cv joints for clicking?

Sometimes those noises under the car can travel and sound like they aren't where you think they are. Wonder if it could even be in the transfer case.

Haven't put my driveshaft on yet, even though my rav4 is a 4 cylinder, it's a lot more fun to drive -

 

No matter what I do with the 4WD ECU unplugged it will not make the noise. So IMO that rules out anything to do with brakes or CV-joints (and I know what they sound like).

I may reconnect the ECU and try a few other tests. My LED verifies there's no rear drive in Neutral so even tho the car is normally parked on a slight incline there shouldn't be any noise when letting it roll because the 4WD won't be engaged.
There'd be no point in "putting it into 4WD" because it does that itself every time it's shifted into any gear, Lock button or not.

So, thanks Jerry for the analysis and diagnosis but now that I've made sure nothing is loose and it won't leave my wife stranded with "parts on the road" as she says, until I can make it repeat more than once a day I'll likely just ignore it. I am however starting to like my rear drive disable/enable switch idea.

 

Just a final follow up to my driveshaft replacement. The ujoints have zerk grease fittings, interestingly (not a toyota one). The center support bearing rubber is definitely stiffer, but still "compressible", just not nearly as easy as the old shaft. Also I drove this thing a couple of weeks or so with no driveshaft installed, ran fine with no trouble lights or engine codes showing up, I did have the connector unplugged behind the glove compartment. No bad snowstorms either, with my luck I was expecting one.

Upon installing the driveshaft, the front gets attached first, then the rear according to the service manual, and it's a good idea to do it that way. (then center) I found that after mounting the front, the back did not line up correctly, probably from spinning the front wheels when I hit the gas too hard, we have a gravel driveway. That's my story anyway
Easy enough to fix, jack up the rear end (which is lighter than the front!) and turn the back wheels until drive shaft lines up.
I don't know if just jacking up one wheel can fix this or not, I have a trailer hitch mounted on my rav for a bike rack, and when I jack up the back end I just jack up under the hitch part which does both wheels. I made sure that the yokes on the drive shaft at both ends were oriented the same way to maintain balance. The other thing I did was make sure I didn't go over that 20 degree angle, which was a pain since I did it myself, but enough blocks of wood make that doable.

No more rumble strips! Next project spark plugs.

 

Congratulations, and thanks for posting back with your results. Also your posts will be helpful for others with the same problem.

 

Hi all,
thanks for the post, I was having exact same issue rumble strips and stopping when warm but after struggling for couple attempts to get the prop off it seems mine is caused by sticking handbrake cable.

As notes others trying to remove your prop from ramps/stands:
The rear is pretty straight forward as you can lay directly under it, the front however is a little more tricky once the rear is off lower the prop to get better access to the bolts to reach the top ones you can pass your arm around under the frame and back up nearer to joint to get better position on the nuts.

Also may well find the prop is corroded to the rear and front diff to split the prop from the rear diff is straight forward as you can lay directly under the join and split it apart with a hammer and bar, the front had me puzzled for sometime until i saw a youtube you can hit the prop with a bar from the front under the engine and over the the frame then hit it off towards the rear of the car!

Tools required 12mm socket and spanner for diff front and rear connections, 14mm for center bearing and 10mm for trays/covers, Hammer, bar

Rav 4 Mk3 prop remove <---- check out at 4m20sec for angle/position to hit prop.