My 2009 XC90 has a loud humming noise that has been diagnosed as a bad rear differential. There is no leak whatsoever. Car has 110K miles. Repair shop is offering a replacement from a 191K mile car with no warranty. Ugh. Does anyone know where a more reliable replacement might be found? Or does any...

One reference- https://www.swedespeed.com/threads/rear-differential-whine.219929/ , there are a few more on the internet. Pinion bearing failure is not that uncommon, there are rebuild kits available with a few write-ups and there are range Range Rover techs familiar with the repair (rear diff is sh...