Grinding sound when slowing down

[Mahwash]

Hi , i got Toyota Avensis Dcat 2011 diesel automatic, grinding sound when slowing down, but no sound when pedal down the accelerator, gears perfectly engage smootely, seems the sound is coming from gearbox side. I have changed the gear oil, still no joy. Any idea would be highly appreciated

[APS]

Can you share more information about the symptoms? Ideally a video or audio recording. 

It seems you suspect the transmission, is that because where the sound comes from or the type of sound? What about when you apply the brakes?

[DerekHa]

Hi Mahwash,

Is it possible the noise you hear, the grinding sound, is coming from the brakes?

Not familar with the Avensis but if it follows the usual modern tranverse engine/gearbox layout your auto box will be on the nearside of the vehicle. Unless you can be certain the sound is transmission related would suggest you have a good look at the front nearside disc brake assembley as it's close to where the gearbox and diff will be located and noise like that can travel through the body of the vehicle.

Otherwise it sounds like an expense coming up you don't need right now.

[Mahwash]

1 hour ago, APS said:

Can you share more information about the symptoms? Ideally a video or audio recording. 

It seems you suspect the transmission, is that because where the sound comes from or the type of sound? What about when you apply the brakes?

You hear the sound only when the gear is engaged, I have checked the brakes, seems fine.  I have made a short video below 

[APS]

3 minutes ago, Mahwash said:

I have made a short video below 

That sounds like a transmission problem. Either something is loose or a worn bearing.  I would try to feel the different components in order to try and locate the source. Feel the engine, gearbox, hub carrier... Obviously, be very careful as you have rotating parts that can quite easily grab hold of clothing, hair etc.

Someone with more experience of this particular model may have a more accurate diagnosis.

[DerekHa]

Agree with APS that doesn't sound at all like a brake problem!

As stated be very careful if your going to try and get hands anywhere the rotating parts they're 100% unforgiving!            I presume your well aware of the dangers as you look to have full garage facilities available to you.

Besides a hands on approach the with the engine, sump, transmission to feel for the vibration that should be present you could try the old "big screwdriver trick". Carefully press the tip of the screwdriver against the sump or the casing you suspect and listen to the handle end, it will pick up the sound like a stethoscope and should give you some indication as to where that awful noise is coming from. I appreiciate you may have already tried this.

Good luck Mahwash