AW55-50SN Gear Noise from Differential/ Final Drive?

wanderdüne · Post by **wanderdüne** » 11 Oct 2018, 08:57

Hi, I'm an interloper on this forum, I am posting about my 2004 XC90 2.5T FWD. I'm posting here because of a shared transmission (AW55-50SN) with the V70 and S60 cars. There were not a lot of FWD XC90 of that era. Don't know if this is ok, but thought I'd give it a shot.

I just bought the vehicle, it currently has ~193K mi. No codes on Vida, runs good and the transmission shifts flawlessly. It does however have some gear noise, from what I understand the differential and final drive are internal to the transmission and it sounds like a differential to me. I had an old 96 Subaru Outback with the same type of sound coming from the rear diff. It is a constant noise at speed, not related to RPM's and the pitch gets higher, but not louder with speed, so I think probably not bearing noise.

It's not terribly loud, but it's there. If anyone has experienced this symptom and could offer a diagnosis, prognosis, action to repair or method to ameliorate this condition I'd be grateful to hear it.

I will be changing out the fluid, which is dark, but not especially burned smelling. I plan to use Idemitsu 1161540, which is JWS 3309 compliant and I'm thinking of adding a half bottle of lucas trans fix in the process.

Thanks

Post by **jimmy57** » 11 Oct 2018, 12:51

I have not seen the final drive get noisy from bearing issues but it surely is possible.
Before that is assumed to be it, the RH CV axle support bearing on engine bracket needs to be checked. You can take out the two bolts and wedge something between the shaft and block to keep bearing out of its saddle and then you can spin it and check it.