2000 XC70 Ongoing driveline issues, diff replacement

[Conkyashley]

Hi all,

This is my first post so go easy on me!

I have a 2000 v70 that was having a whirring sound for the last year or so. Mechanic thought it was the viscous coupler, so we replaced it. This didn’t solve the issue. My mechanic installed a gently used rear differential yesterday. Whirring noise is gone and it generally feels better. However, now whenever I hit 38-49 mph there is a moderate shaking from underneath the car. I strong vibration that sticks around until I hit 50mph.

Any idea what could be causing this? I had no vibrating before the switch happened. They suggested I drive it for a week and see if things settle into place.

Tires replaced about 6,000 miles ago and in good shape.

They suggested that I might need a new driveline which I am hesitant to jump into. Any thought or suggestions would be greatly appreciated.

[Clemens]

What does gently used mean? These AWD systems can fail under 100k if treated improperly. So ome out of a donor car or sthg. similar might be shot.
Is the rear differential coupled to the driveshaft? If so, the driveshaft might have a shot joint or lost it's balancing weights.

[abscate]

Hi all,

This is my first post so go easy on me!

I have a 2000 v70 that was having a whirring sound for the last year or so. Mechanic thought it was the viscous coupler, so we replaced it. This didn’t solve the issue. My mechanic installed a gently used rear differential yesterday. Whirring noise is gone and it generally feels better. However, now whenever I hit 38-49 mph there is a moderate shaking from underneath the car. I strong vibration that sticks around until I hit 50mph.

Any idea what could be causing this? I had no vibrating before the switch happened. They suggested I drive it for a week and see if things settle into place.

Tires replaced about 6,000 miles ago and in good shape.

They suggested that I might need a new driveline which I am hesitant to jump into. Any thought or suggestions would be greatly appreciated.

It’s possible to remove the driveshaft on these cars and temporarily run it in FWD mode. I think I would try that to isolate it to the rear drive section.

Your first post just made infamy as a prime example of To read and follow our post guidelines

Thank you!

[Conkyashley]

From what I understand, when they pulled the diff out of my car they were shocked it was even functioning. The rotating piece inside was barely moveable by hand. The new piece was smooth and infinitely better than what I had in the car previously.

They have suggested that the driveline might need complete replacing which seems like a big jump considering there are so many parts in that system that could have failed.

When i follow up I will ask them to check the balancing weights and possibly remove the AWD function. I just hate to do that because that is one of the main reasons I have this car!

[abscate]

You can get good used replacememt AWD stuff reasonably, no sweat.