Yep sir,

Axle housing ears and spring seat with rubber bushing 1929 - 1957 Chevrolet Master Parts & Accessories Catalog
Prevents binding when leaf springs compress and telegraphing of road vibrations into truck/car body.
Only on torque tube/Closed Drive Shaft equipped trucks and cars.
Different angle pic

Benefits of Torque tube/Closed Drive Shafts
Jim Carter Viewer Tip
Absolutely impervious to rear spring wind up, when used on soft ground