gasoline tank vs petrol tank

gasoline tank and petrol tank both are nouns.

Word	Noun	Adjective	Verb	Adverb
gasoline tank	Yes	No	No	No
petrol tank	Yes	No	No	No

As nouns, gasoline tank and petrol tank are synonyms defined as:

gasoline tank and petrol tank: a tank for holding gasoline to supply a vehicle

Other synonyms of gasoline tank include gas tank.

gasoline tank (noun)	petrol tank (noun)
a tank for holding gasoline to supply a vehicle	a tank for holding gasoline to supply a vehicle