drive line vs drive line system

drive line and drive line system both are nouns.

Word	Noun	Adjective	Verb	Adverb
drive line	Yes	No	No	No
drive line system	Yes	No	No	No

As nouns, drive line and drive line system are synonyms defined as:

drive line and drive line system: mechanism that transmits power from the engine to the driving wheels of a motor vehicle

drive line (noun)	drive line system (noun)
mechanism that transmits power from the engine to the driving wheels of a motor vehicle	mechanism that transmits power from the engine to the driving wheels of a motor vehicle