auto maker vs car manufacturer

auto maker and car manufacturer both are nouns.

Word	Noun	Adjective	Verb	Adverb
auto maker	Yes	No	No	No
car manufacturer	Yes	No	No	No

As nouns, auto maker and car manufacturer are synonyms defined as:

auto maker and car manufacturer: a business engaged in the manufacture of automobiles

Other synonyms of auto maker include auto manufacturer, automaker, car maker, carmaker.

auto maker (noun)	car manufacturer (noun)
a business engaged in the manufacture of automobiles	a business engaged in the manufacture of automobiles