ORIGINAL: Sport_Pilot
Many high performance automotive bearing inserts contain aluminum alloys.
While some may have a small amount of aluminum it would not be near enough to call it an aluminum alloy. They call the alloy babbit. Perhaps the shells are aluminum, but the bearing surface is babbit.
Babbit use has been discontinued for some high load/temperature rod bearing inserts. It is too soft to hold up to the pounding & heat.
Harder alloys that contain aliminum, tin & silicon are employed for some higher load applications. Some of the "embeddability" of the soft babbit has been traded off for the higher load carrying properties.
Since the embedability properties that the added tin impart to the aluminum/silicon alloys is not needed in our applications, the aluminum/silicon allloys used in the conrod construction suffice.
Federal Mogul uses an "AT" prefix to denote aluminum/steel bearing insert construction.