I have a shop telling me that I need to replace the front diff on my LX470 100 series. Is there a way for me to tell for sure that is needs replacement? I am going to probably replace most of the front end parts because it has 280K miles on it and most bushings/CV joints are worn out. It has never been off-road and has been babied (at least by my for the past 5 years) but it's time for a refresh...