while the 2007 Outlook XR AWD was in for service, dealer also wanted to do 4 wheel drive transfer case service for 194.95 and rear differential service for 159.95. Car has 57k and they said it should be done at 50k. Any thoughts from someone who has had this done? I'll probably skip the dealer doing it and go to my private mechanic. They also mentioned an additive for the rear diff that binds to the metal - not sure what that is.