Say I have 100K in hand and I want to buy a 120K car.

Scenerio 1
Interest rate = 3%
Down payment = 100K
Loan amount = 20k
Tenure = 5 years

Total interest pay to bank after 5 years = 3K


Scenerio 2
Interest rate = 3%
Down payment = 20k
Loan amount = 100k
Tenure = 5 years
Total amont of interest pay to bank after 5 years = 15K

Balance money put in FD = 100k - 20k = 80k
FD interest = 4% (compound)
Total interest in bank after 5 year = 17.3k


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Is my assumption correct? Does it make more sense to put min down payment for car? And put the extra money else where with more than 4% return?