Carrier bearing. It wont really wiggle untill under load. Its in a cage. When the rubber goes out it will still work, just move under load. Make sence. Now when the whole mount breaks the carrier bearing will wiggle then. Ive broken enough and replaced enough to know to spend the money for the good polly unit from inlandempire drive shaft.
http://www.iedls.com/Center-Support-Bearings/1958-64-Chevrolet-Cars.asp Same one I use but I get them from Show Cars Automotive they are about 110
The Jalopy Journal
