[faisalq69]

Suddenly had a grinding noise coming from the mid of the vehicle. Drained and replaced fluids in both transfer case and rear differential.

Noise was still there, mechanic says it could be an issue in-between the gearbox or transfer case and will have to drop both to further investigate.

Vehicle is 2006 ACA31 4WD

Please help if anyone has had a similar issue

 

[Foryota]

Suddenly had a grinding noise coming from the mid of the vehicle. Drained and replaced fluids in both transfer case and rear differential.

Noise was still there, mechanic says it could be an issue in-between the gearbox or transfer case and will have to drop both to further investigate.

Vehicle is 2006 ACA31 4WD

Please help if anyone has had a similar issue

Welcome! Sorry to hear about your trouble. We’ve had several threads recently about noise from “down under” (not Australia!) which in those cases has turned out to be worn/fused/sticking U-joints for the rear driveshaft (propellor shaft). The bad news is that Toyota doesn’t list a replacement part for the joints themselves, requiring a new driveshaft at significant cost. In these cases some members who have confirmed that it’s the joints have gotten a replacement shaft from a newer wrecked RAV, rather than a new one. Some have had luck with 3rd party parts. I suggest you have the joints and shaft checked out to see if that might be the issue. Hope you find an affordable solution!


2012 RAV4 Base FWD.
Upgraded to large front brakes and 3rd row rear springs.

 

[DL175]

You can disconnect the 4WD ECU to see if you get the noise still. The 4WD ECU is behind the glove box. There is also a TPMS ECU that looks similar so don't pull the wrong one out.

 

[faisalq69]

Welcome! Sorry to hear about your trouble. We’ve had several threads recently about noise from “down under” (not Australia!) which in those cases has turned out to be worn/fused/sticking U-joints for the rear driveshaft (propellor shaft). The bad news is that Toyota doesn’t list a replacement part for the joints themselves, requiring a new driveshaft at significant cost. In these cases some members who have confirmed that it’s the joints have gotten a replacement shaft from a newer wrecked RAV, rather than a new one. Some have had luck with 3rd party parts. I suggest you have the joints and shaft checked out to see if that might be the issue. Hope you find an affordable solution!


2012 RAV4 Base FWD.
Upgraded to large front brakes and 3rd row rear springs.

Thanks for the insight, this is exactly what the mechanic said, he suspected it to be propeller shaft coupling, but that seemed to be ok.

Mechanic said we will book it in for inspection of centre diff

 

[faisalq69]

You can disconnect the 4WD ECU to see if you get the noise still. The 4WD ECU is behind the glove box. There is also a TPMS ECU that looks similar so don't pull the wrong one out.

On diagnostics, 4WD ECU appears to be ok

 

[SoNic67]

You can disconnect the 4WD ECU to see if you get the noise still.

The prop shaft rotates all the time, no matter what 4WD ECU says.

Mechanic said we will book it in for inspection of centre diff

There is no central differential in this car. Just a rear differential (electrical controlled) and a transfer case mated to the transmission.
Between them is the prop shaft with two U-Joints. The prop shaft also have a carrier bearing in the middle. That middle bearing can make noise too.

Take out the whole contraption and drive the car only FWD (no problem, the 4WD light on dash will turn on and disable the 4WD automatically), see if there is any noise left. If the noise is gone, the prop shaft is the problem.

The U-Joints were replaced by some industrious people (as opposed to buy a new shaft):

 

[DL175]

The prop shaft rotates all the time, no matter what 4WD ECU says.


There is no central differential in this car. Just a rear differential (electrical controlled) and a transfer case mated to the transmission.
Between them is the prop shaft with two U-Joints. The prop shaft also have a bearing in the middle. That middle bearing can make noise too.

If the driveshaft is turning all the time that means you have 4WD all the time. Isn't this on FWD most of the time?

 

[SoNic67]

If the driveshaft is turning all the time that means you have 4WD all the time. Isn't this on FWD most of the time?

The electric coupler is at the rear differential.
So front wheels and prop shaft rotates together, rear wheels together with rear differential, and right there is the coupler. People call it "viscous coupler" but is not viscouus, is electric.
It has that famous special bearing that needs to be replaced:

Electromagnetic coupler bearing replacement

The rear drive actually engages every time you start off. One diagnostic that's easy to run is disconnecting the connector from the 4WD ECU behind the glove box. Then driving down the road everything in the rear will still be turning but not under power. With the car on jack stands only the...

www.rav4world.com

 

[faisalq69]

Hello All, thank you kindly for your inputs, to update you, the issue was broken/damaged bearings in the gearbox which ended up damaging the clutches in the CVT transmission.

A re-conditioned CVT transmission is being fitted now as we speak.

Thanks again for everyone's advice

 

[Foryota]

Hello All, thank you kindly for your inputs, to update you, the issue was broken/damaged bearings in the gearbox which ended up damaging the clutches in the CVT transmission.

A re-conditioned CVT transmission is being fitted now as we speak.

Thanks again for everyone's advice

Thanks for reporting back. Too bad you need a rebuilt transmission but at least they found it.

So you know, you don’t have a CVT automatic - you have a normal 4- or 5-speed automatic with your 2006 model.


2012 RAV4 Base FWD. Upgraded to large front brakes and 3rd row rear springs.

Link to SAE J2807 test description

That Dam Towing Test: New SAE Trailering Standards Explained

The new standards ask: Can you climb the Davis Dam grade?

www.caranddriver.com