Yes, both 15"......55 and 56 Chevy.....but centers are different between 49-54 and 55-56. 49-54 centers had clips to accept the hubcap. 55/56 accepted either dog dish or full wheel cap.
54s have the same type centers as 55s, meaning they both have the outer "'nubs" instead of the "inside clips" . This only applies to cars, not trucks.
54's also had the ears that held "dog dosh" caps. Up to 53 had the clips. Some had rubber dust seals in the slots between the inner and outer rims.
So the 54 wheels have the nubs on the rim for the 55/56 full wheel covers? Good to know. My 54 never had the original wheels. The ones I have now are 53 with the clips for the earlier hubcap.
I find it hard to believe that 54-56 are the same part # cause the 55's had riveted centers and the 56's were the first year for welded in centers, which meant you could go tubeless, but anything is posssible...Squirrel should know though
55's with full wheel covers had little bumps on the outer rim part that the wheelcover would lock onto, and I'm fairly sure '54 did not have that, also with the differences between welded and riveted construction. I've also heard that '55 Corvette used welded wheels a year before passenger cars got them. No reason you couldn't interchange them on the car, but I think they all have some unique differences.
54-56 basic the same. 55-6 had nubs to hold the full wheel cover. Vette were different. I just don't remember the differences.