You can read my original thread post below and read through the pages of discovery, but I’ll save you google searchers some time and give you all the details in the first post.
So, I’m a service writer and partial owner of an independent family owned and operated Volvo specialist shop that’s been in operation for over 30 years. When I encountered this problem on my S80, I went about finding a solution. Over the next 3 years we not only solved the issue, but now offer rebuilt differentials that we ship all over North America for all the effected differentials from the 07+ years on.
So, lets start first with the technical details:
The primary fault seems to be the pinion bearing on the differential fails and fills the fluid with metal causing other bearings to fail and makes the terrible noises that you can listen to in the videos attached below. The differential that has this failure was used in the first generation Volvo Xc90, 2007+ S80, 2008+ Xc70, 2010+ XC60, and the 2011+ S60. It was also used in the Land Rover LR2, as well as some Jaguars and Fords. This was part of the FoMoCo brand extension/cross pollination of the Haldex AWD system adapted for other vehicles. They didn’t all get the exact same differential and they aren’t interchangeable, but the guts and bearings are mostly the same. What is puzzling, is some car were much more common to have failure than others. Logic would say the Xc90 V8 would be the car most likely to experience failure as it has the most HP/TQ as well as the most weight, but no, it’s one of the less common ones. Most common are the Volvo’s built on the P3 Chassis — clink on the link for the wikipedia article of the cars included in the platform.
When I discovered the issue, we went about solving it. What’s not disclosed in the forum posts below is all the technical steps we’ve taken to offering the best rebuilds available, not to mention the thousands upon thousands of dollars spent in R&D and obtaining or creating the tools necessary to offer a proper rebuild.
In the video below I have a 2008 Xc70 up on a lift pointing out the active on demand coupling as well as the differential. To date, the only time I’ve seen a Active on Demand Coupling need to be replaced at the same time as a differential was due to negligence on the part of someone doing a repair. OAC’s can fail, but almost never because of a differential.
The noise is especially noticeable when letting off the throttle and the vehicle is coasting around 50 mph. Depending on the load in the differential, the noise can be quieter or even come close to disappearing
Options for repair that I know of:
Install a used differential:
A used differential is just as likely to fail as the one you have and could be as expensive or more expensive than my rebuilds.
Install a new differential:
Volvo has a lifetime warranty on parts installed by them. In some regards, this is the best value for the dollar, but the new differential carries a price of over $4,200, and dealers are starting to require the Active On Demand Coupling to be replaced with the differential to be covered under warranty, which brings the cost of repair up to close to or beyond $9,000. That “genuine life time warranty” comes with quite the price tag, sometimes equal to or greater than the value of the vehicle!
Convert to a front wheel drive and remove the rear axles and differential.
Options from me:
I’ve rebuilt hundreds of these by now and they’ve shipped all over the country and have never had one come back for a bearing failure. Cost is $1,500 and it includes freight to you as well as a return label for the core. There is an additional $500 core fee refundable when we receive your old differential. I ship a differential to you, you install it, or have it shipped to the shop of your choosing, and the old differential is shipped back for a refund. Very simple and easy. My rebuilds come with a life time warranty for as long as you own the car.
In other options, you travel to my shop and we install an already rebuild differential and you will leave approximately 5 hours later with a much quieter car for just under $2,100 total with parts, labor, differential, fluids, alignment, and tax all included.
You can send me a message here on the forum or get in touch with me on my business phone number at 434-332-6211 and ask for Justin.
You can also email me at my work address here
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Here is my original post from 2013.
I’ve got a 2010 S80 T6 with 92K on the clock
I’m experiencing a lot a whine out of the rear differential around 40 MPH. Go 10 MPH higher and lower and the noise almost completely disappears.
I’ve verified the fault is the differential on a lift and eliminated the active on demand coupling and angle gear from the equation. I drained the differential and active on demand and checked both fluids to check for contamination and both looked fine without any sign of debris. I replace both fluids with fresh, and naturally there is no change.
Going by Volvo’s parts diagrams they only the complete unit and there is no listing for any internal parts or bearings. I believe my “Finale Drive” is 36001787, and retails a spot over $4,200. Checked around used and the best price I’ve found is $1,200. If I pull it apart I’m pretty certain I can get a custom bearing for about any application, but has anyone tried pulling one of these differentials apart yet?
It’s almost ignorable since it’s only that certain speed range, but it certainly bugs me. It doesn’t bug me quite enough to spend $1,200-4,200 though…
Anyone else experience any similar issues?