Car Loan Credit

How will paying off a car loan affect my credit?
After 18 months, I owe about $6k on a $15k car loan. I want to pay the entire thing off with one big payment, but am wondering how this will affect my credit. Should I pay most of it, say, $5k, in order to get a free extra months of positive reporting?
paying things off early wont hurt your credit rating , it will only improve it . i always paid things off early and i havw an excellent credit rating,