It's my understanding that when GM started making them in the 50's they went by "Suburban Carryalls" (both names together). The 1961 catalog called them "Suburban Carryalls"
Then in the late 60's it was shortened to just "Suburban". But the earlier versions seem to use the "Suburban" and "Carryall" names interchangeably. I may be wrong but thats how it was told to me.