rear diff. adjustment costs?

[nh98gsx]

i have been getting a coast down howl, i believe that it is from the rear diff. does any one know approx. how much it should cost to have a shop open the rear diff and adjust the shimms in the rear diff? Also while they are in there is there any thing else that i should have them do or replace?

 

[Diz]

This noise is not normally something that occurs and is then adjusted to fix it. There is probably something worn out or else something like the pinion flange came loose. (In my experience.)

 

[nh98gsx]

say it is a pinion flange or bearing how much am i looking at to have some one open the rear diff and replace either. i am not looking for parts cost but labor costs.