Differential mounts?
 

They are NOT as simple as you think! I am a DIY'e and I did the diff mounts myself. It was a BEAR of a job. I did buy the tool neccessary to change them (around $100) and a few people on this site has made their own but, it is time consuming. Specially for a first timer. BTW, there is a picture of the tool, in the performance catalog. Don't even think of doing this job without this tool or your self made tool because the bushings will not come out, I promise you! Get a quote for the installation from your mechanic and then go from there.
Do a search o the topic.
Good luck!;)

OOps!
 

Made a mistake!
This is supposed to be a response to jrd: Tranny experts: what do you do about a leak in high milage tranny (or something to that effect).
May be the moderator can tranfer this treat. Thanks!