Loud noise when rolling back slowly, engine on or off doesn't matter

[exxczyk]

Hi all, I'm hoping you can help with a very jarring noise my 2010 CX9 GT started making but only when moving backwards very slowly.

-Engine is off
-Transmission is in neutral

Roll back even an inch and it makes an incredibly loud vibration type of noise. But start rolling fast enough backwards and it stops.

I can also reproduce it by raising either front side of the car and spinning a wheel (while the opposite side is still on the ground) so it's definitely not directly one wheel.

Any suggestions would be greatly appreciated.

Thanks
Matt

 

[youri]

Have the brake inspected (or do it yourself if you have the skill). My Cx-9 was doing a bad screeching when backing only and it was a clip that had detached and was rubbing when going backward.

My sound was different than yours but the symptom was the same. It could be something else related to the drivetrain but the easy place to check first are the brakes

 

[exxczyk]

Thanks Youri, I ruled out the brakes since I can reproduce this sound with the car stationary by lifting each front wheel at a time and spinning it. The sound is definitely somewhere in the drivetrain.

 

[youri]

The other thing i was wondering is if it could be a symptom of the common transfer case issue in those model year ( if it is AWD).

 

[exxczyk]

Yea, it is AWD

I had the transfer case replaced many years ago and have had regular checks to make sure the oil has been ok so I'm hoping it's not it. Also no oil leaks anywhere that I can see, last time there was a puddle of thick oil under the car when it failed.

I did notice that it is making this sound rolling forward now too.

I have a mechanic appointment in a week so will find out for sure then. Doesn't seem to be anything I can get at to fix.