bad credit loans monthly payments

Can i get a car loan with bad credit and no down payment?

what would be the interest rate, and monthly payments for a loan for $18,000?

Very unlikely.

No lender will give someone an $18,000 loan for a vehicle who has bad credit and no down payment. At least not without a quality co-signor and strong income.

99 percent of time, situations like this end up in my office and eventually end with a repossession.